The vanilla classes Wizard and Sorcerer have IMO fallen way behind when compared to all the power creep that took place in recent years. Sorcerer has the upper hand in that it can multiclass into paladin or BG and has more uses of IGMS + other useful spells. Many reworked/new spells were added over the years but they were either not good enough or nerfed to the point of uselessness.
I welcome more people to say their piece as I doubt I have the eloquence or precision to address every point.
I'll start with what was mentioned in another thread by changes wizards get, and why they are good or bad.
8 distinct SF/ESF perks
Arelith specific summons and -streams
wild mage path
shadow mage path
8 distinct specialist subclasses
arcane flux
custom and updated spells
spellmaggedon
Spell Focuses
Abjuration: Really good and doesn't need to be maxed out to get usefulness against force spells (IGMS, Bigby etc), its epic spell is one of the more useful things a spell focus grants in terms of sheer utility, being able to block scrying, grant area denial and block teleportation. It also boosts your Dispel power.
Conjuration: Conjuration is an excellent PvE tool early on to boost your Summon Creature by +1, the boosts it gives to summons is also great, and it boosts useful spells. -yoink is one other great utility spell that can ease the life of the caster severely if used correctly. The greatest downside of Conjuration is that its power in the form of boosting summons is rendered null the moment someone casts WoF.
Divination: The DCs of spells boosted by Divination are not good, Power Words are Underpowered Words in terms of power compared to spells of the same level. The investigation and aura bonuses are neat. All of its usefulness is concentraded on -scry, which is a spell so great people are constantly calling it to be removed or reworked. Divination is primarily a RP spell focus.
Enchantment: Neat roleplay passives in the skill boosts, useful empowering of some spells, the dominate two creatures at a time is niche. The spells that are boosted by enchantment are typically good, but they all fall flat vs mind immune enemies, be it PvP or PvE. While Mind Blank can be breached, Clarity is greater of an issue even with its cooldown.
Evocation: Necessary component for Hellball, some of the Bigby spells are REALLY good, the boosts to some summons are a big whatever. That it enables the casting of Hellball without taking damage is the winner here, and part of one of the few spell combos a wizard or sorcerer can do that is threatening.
Illusion: Worse Enchantment with all of its weaknesses, its DC spells are typically a worse version of another enchantment spell with the exception of Weird. -project_image is really good but its been made weaker with the implementation of parrot bottles and wisp bottles. Summon Shades is an interesting niche spell but only works vs certain unprepared targets.
Necromancy: I don't play necromancers, but this spell focus looks so bad in comparison to Conjuration. The spells are not necessarily bad, the death spells are blocked by a death ward which can't be breached, many others are denied by NEP. If nothing else, if their undead minions get a WoF the caster can pump out more easier than Conjuration.
Transmutation: Very much an utility school, not a lot of DC spells and the custom effects of boosting Zoo spells is only useful for builds that need 4 stats or more to function, a lot of the empowered spells are divine casters only. The greater focus -teleport is okay but portal lenses are not that expensive, ditto for the epic portal it can create.
From the above, Abjuration and Evocation are the only POWERFUL spell focuses to take, Enchantment and Illusion fall behind if made near useless by mind immunity. The others are either too gimped or do not offer nearly enough to warrant taking focuses in them.
Streams
Honestly? The concept is amazing, most of the summons are good. Some are not.
Summon Creature I-IX: Good for what they do.
Planar Conduit: Excellent for PvE, a joke in PvP since they cannot be recast, I do not like this duality as its one of the only ways to do PvE content as a wizard or sorcerer while eating up a feat thats purely for PvE. Dedicating ESF Conjuration to make PConduit useful and then getting PConduit itself is not really appealing unless all you want to do is PvE and otherwise be a WoF away from having four feats denied. The worst part is that you can't actually make use of streams with this, it's a huge metagame tool, if you play a good guy trying to pretend to be a bad guy, you can't ever use PConduit, and vice versa.
Mummy Dust: Same as the above. Great variety though, good work there.
EDK: Its been a while since I last had a proper look at EDK, I witnessed an EDK Dracolich which I assume to be the strongest variant be bodied without much issue in a few scenarios. For a short lasting one time use summon, it should be far more devastating than a Gate. Another problem is that the dragons are big and struggle with pathing/attacking, nerfing them indirectly.
Wild Mage Path
I have no comment to give here as I do not like wild mages and do not play them. I welcome those that would speak more on it.
Shadow Mage
Shadow Mage has huge flaws, one is that the only way to reliably be deadly in PvP involves Evocation (with the use of Hellball), the other is that DC spells are not good in a server where you can easily obtain +40 saves. Having tried a shadowmage that gets 42 INT (an unoptimal number that requires +1 Great Int), 41-43 DCs really do not matter in PvP or PvE when epic mobs are often immune or have +40 saves.
Shadow Mage is an awesome concept that I would wish was better defined, right now its giving up on one of the most powerful schools (and transmutation DCs but those don't matter) in exchange of just +2 DC on Illusion/Enchantment/Necromancy, that's 10 spellcraft points worth. Boosting the DCs to a point they actually matter and making Shadow Weave harder to dispel by non Shadow Weave (while making normal Weave casters harder to dispel) would be an interesting addition too. Perhaps unique spells/mechanics that normal Weave casters do not have.
Specializations
Here I'll say which specializations are good, and which are bad, and maybe how to make them better.
Abjuration(prohibited Conjuration): BAD. Do able if necromancer, otherwise PvE suffers greatly and you will rely on other people. +1 resistance vs dispels is not bad, the 28 level effect while good is not worth missing discipline, +2 vs spells is redundant since you can get +40 saves vs spells as is, +2 breached effects is the only good thing to take from Abjuration spec, and it won't always apply vs enemies without sufficient breachable wards.
Given the sacrifice of conjuration, any summon presence are unothordox summons (that typically aren't good) or necromancy, an epic unorthodox summon with its own perks and progression could alleviate this. Besides that, the boons are not enough to warrant a specialization, I would reduce the level 28 effect to 27, and increase the resistance vs dispel by another +1.
Conjuration(prohibited Transmutation): BAD. Even if your summons have SR, they are not invulnerable to scrolls much less WoF casters. It both is and isn't a QoL specialization for better summons as they get perma haste but at the same time you are locked out from buffing them with Mass Zoo spells. What really makes this a terrible specialization? NO HASTE SPELLS. Auto quicken is mandatory, you take a specialization that requires potions, someone hasting you or three epic feats for very little benefit.
Honestly, the only way I see this specialization becoming good is if its boosts to summon so powerful (while being very resistant to WoF) or changing the prohibited school(which I don't know if its possible, I believe it is), at least the former actually defines them as the defacto summoner expert who doesn't become the joker upon a WoF.
Divination(prohibited school Illusion): ACTUALLY ALMOST GOOD? Better True Seeing on demand, harder to detect 4 minute scry, +7 DR premonition, turns/level Clairaudience/clairvoyance. Wow, this is actually, not bad. You still will get breached from Premonition on most times but you can catch +5 weapon friends off guard. You lose Improved Invisibility which kind of sucks but it can be patched with consumables even if they're clunky. It is not a bad school for someone who wants to KNOW things.
Yet, I still feel it could use something more in the ways of PvE/PvP, perhaps DC or extra mechanics to Power Words to make them more useful as it stands they are really not good spells.
Enchantment(prohibited school Illusion): GOOD. The one specialization that makes Wizard almost as good as a bard for a support role, exclusively because it gives +2 damage/AB and about +4 to skills. You are a worse bard capable of spewing IGMS, be proud of yourself, it's all downhill from here otherwise. Coupled with Enchantment focuses, you can get very high Bluff values too. Missing out on Illusion is not a huge deal much like Divination.
A way to make their offensive spells better would not be unwelcome, as they still suffer from people with high DC and immunities.
Evocation(prohibtied school Evocation): CIRCUMSTANCIALLY GOOD. It is only good if you use necromancy summons in place of conjuration, it is otherwise in the same trap as of Abjuration regarding PvE. It boosts two of the best spells the wizard has, the DC of Clenched Fist and 1 more 2d6 for IGMS, thus making the go to's of a wizard even better.
Same as abjuration, if given more alternatives to summons, it would be good, boring but good.
Illusion(prohibtied school Enchantment): BAD. If you don't plan on taking Enchantment, this is Generalist but better. It has neat disguise mechanics but otherwise it really does not do a lot, +54% ish concealment for a level 27 wizard? At least all it misses out on is Mind Fog.
Similarly to Enchantment, empowering their offensive illusion spells would go a long way, or new/enhanced spells that go around mind-affecting wards in the sense that they propose an outside illusion similar to Shadow Conjuration spells. A more unique RP gimmick would also be fantastic, since -project_image lost much of its value and the clone is niche at best. Perhaps a Mirror Image spell that functions as if giving concealment and spell mantle?
Necromancy(prohibited school Divination): BAD. Its a lot of boosts to summoning undead similar to Conjuration, if you take this you are likely not making ample use of other summons as is. Again, similarly to Conjuration, these boosts all fall flat when a WoF caster steps into the scene, this specialization at least has the edge they can spam passable summons with more ease than Conjuration, and they all have SR, thus making WoF scrolls a lot less reliable. Loss of True Seeing is painful if you want to detect invisible/stealthy people.
Like Conjuration spec, this puts all their eggs into one basket and it's not that great of a basket. Giving their other necromancy spells more use and power would go a long way to make this a cool specialization.
Transmutation(prohibited school Conjuration): MEGA BAD. Oh man, making this specialization focus entirely on Tenser's Transformation is not a good idea, honestly the boosts this gives Tenser's should be vanilla. The +1 to Zoo spells is a token gesture at best to boost your summons- oh wait you don't get Conjuration, nevermind. There's not much else to be said, it's the single worst specialization.
Generalist: BAD. Its only perk is that you get to use Mind Fog for illusion spells(illusion is just worse enchantment anyway), a slightly better chance with Arcane Flux(purely a PvE gimmick), and get to cast Invisibility.
Honestly, if the other specializations are made good, Generalist could get the +1 slot per level they typically miss out on and call it a day. Probably.
Arcane Flux
Speaking of Arcane Flux, it's a PvE exclusive feature that rewards the wizard for spamming cantrips. When I was leveling this as a lowbie, I procced it so few times it was worthless, on epics I proc it maybe once per dungeon and it's still worthless because our offensive spells suck lmao.
custom and updated spells
spellmaggedon
Two in one. Many spells were buffed over the time, but any time they were "good" they were considered too good and nerfed into uselessness again. Most of the new spells are either not good enough or flat out bad. I could go at length about every spell but honestly I don't have the patience to write up that much (I already wrote so much as is) when there's a chance developers won't agree and will just toss it into the trash.
FINAL WORDS
Wizard and sorcerer have no killing power outside of summons(that can get WoF'd easily) or a carefully laid out Hellball Time Stop IGMS combo. Most of their features are very basic lowpowered QOLs, miss the mark or are ineffective at what they do. I have seen people spam Healing Draughts/Shield potions to keep themselves alive against IGMS and the caster ran out of IGMS before they died.
DC spells are meaningless, there are too many ways to boost saves and get immunities. The mechanic that increases DC on a spell upon repeated casts is interesting but you have very little time to try that before you're cut down or run out of spells. Save or die spells suck for the other party, perhaps making them powerful in ways that are not "die" would make them more acceptable while being significant.
Low AC and survivability, unless you do a Palemaster or Divine Shield build or some gimmick with monk(which will no longer work after the monk rework goes in?). Mages are in theory glassy support casters that have the potential to apply very powerful bursts within their vancian limitations, right now they're just glassy bad supports that pale in comparison to bard and the likes. Being granted more interesting means of survivability that are mutually exclusive to PM and Divine Shield without diverting to other classes could be interesting as a feat investment (besides EMA, which on its own is not enough and PM/Div still benefits from it).
Spell bloat, there are LOTS of spells but too many are not good. If there's an interest from a dev I could list the ones that IMO are not good.