Alternatively, if you're not looking for a primary melee bard (which has fallen a little out of favor in recent years), you can refocus some of your feats and gear spread towards survivability.
In particular, this is a problem:
No GEar AC is 12, HP are 210
With Gear, AC is 27, HP is 270
Not just for you, but for any party you're in, because all benefits of bard song and penalties of curse song end if the bard providing them dies.
Quickly, I can see a few things you might remove to improve your survivability, entirely without any stat reallocation:
Extra music and lingering song are comfortable feats, but not necessary by any stretch of the imagination. Improved dweomercrafting is the worst offender, however. It does exactly nothing for your build.
From the Wiki on Dweomercrafting:
One Magic Tier is gained for each of the following:
12 levels of Cleric/Healer, Druid, Elementalist, Favored Soul, Hemomancer, Shaman, Shadow Mage, Warlock, Sorcerer and Wizard (not Spellsword).
Having 24 levels of these classes adds a second Tier.
21 levels of Bard, Hexblade, Paladin, Ranger and Spellsword.
Having 28 levels of these classes adds a second Tier.
Dirgesinger is treated as Bard for the purpose of dweomercraft tiers.
Scribe Scroll, Brew Potion or Craft Wand feats.
Skill Focus or Epic Skill Focus feats in Craft Mastery.
Improved DweomercraftIng feat.
Forge Domain (Cleric)
So to recap: you get 1 Dweomercraft level from 21 bard, another from 28 bard, and a third from brew potion.
So the first thing I would do is scrap improved dweomercrafting and lingering song, and use these feats to slot in expertise and improved expertise. These buttons are, in a lot of cases, 5 or 10 free AC for a bard, respectively, but you'll need to reapply after casting. Still, as a bard, you will always be a priority target in group fights. Having improved expertise lets you pull a considerable chunk of AC out of nowhere whenever you get focused.
You may also consider stripping out extra music, and finding space for epic skill focus: discipline in your build. With this feat, decent gear, and the skill bonus from song, you'll be relatively hard for most people to knock down, even if you don't have very much strength.
Which brings us to gear.
Songssword Guard Armor
Displacer Beast Cloak
Beguiler's Crown
Adamantine Bracer of Persuasion
That belt that protects you from poison and I added strength (Encircling Snake?)
Lantanese Ring
A ring with AC +2, Cha +1, INT +1, Perf+2 , Spot +2
Apart from the songsword's guard, I'd replace all of this.
Beguiler's crown doesn't offer you a lot; an extra cast of a level 5 bard spell is about it. I would replace this with a headband of protection. 26 SR will offer you reasonable protection against a lot of scroll-based spell effects, and if you're keeping GSF:abj, the combination of the headband of protection and a shield potion will remove the first 7 damage of any force damage effect, at a minimum. If you don't want to fiddle with shield potions, pick up an adamantine helmet instead (though I personally think the shield potions are worthwhile, especially with the abj focii).
Likewise, the adamantine bracer of persuasion doesn't help as much as you might like. You aren't aiming to max out any of the skills on it (leadership is the only one you're pumping, and you can get it to the maximum useful skill of 50 without these bracers). These (and most of your gear slots) should be replaced with basin crafted gear. On that note, I'd toss out the lantanse ring and the +2 AC ring. The +2 AC on the second ring won't stack with the helmet, and the lantanese ring is an inefficient item.
Replace these with enchanted scholar's rings (you can buy them at the arcane tower, and it's not too hard to put +2 discipline, +1 constitution, and +1 universal save om them), for an end item with +1 con/+1 unisave/+5 lore/+2 discipline in both ring slots. As you are able, you can apply a masterwork bejeweled rune to each of these for extra stats.
Like the lantanese ring, the encircling scale is an inefficient item, especially post nerf. It gives you saves against poison, but with proper gearing, your saves should be fine anyhow. Make something in the basins that covers your useful skills (I'd pick discipline, spellcraft, lore, listen, and perform, plus constitution and universal saves, but you can grab other skills). Morgy has already adequately explained why boosting your listen is good.
Make something similar to replace the displacer beast cloak and the adamantine bracers of protection, and the amulet. As with the rings, you can make better stuff eventually, but these will be cheap, easily made items that improve your survivability drastically.
Boots will be a little trickier, because it's important for your boots to have a +1 AC enchant on them. My personal preference here is to do 1 point ac, 2 discipline, 2 spellcraft, +1 to your weakest save, and +1 to con, and then to use a masterwork tailored rune to add a second stat or another skill, to taste.
Regarding spot/search:
I would make a separate gear set for this. You can now easily swap loadouts with a quick use of the -loadout command, so you can simply hotkey your "combat" loadout, and your "guard duty" loadout.
Regarding AC: you should be sitting around 52-54 AC outside of expertise.
Get a shield. The extra AC is good for you. The one you want is probably the +4 large shield from carpentry.
Get tumble. The extra AC is good for you.
Buff your dexterity to fill out the songsword's guard. Because you're running a base dex of 8, you might need an ioun stone and 1 point of dex enchanted on an item. Your target is 18. Songsword's guard comes with 2, cat's grace will give you 5, and an ioun stone another 2, for 9.
When in combat, make sure to keep a wand of barkskin around. Mass haste is part of your spellbook, and your casts of it last 6 minutes each, so you should be hasted for most fights.
If you do all this, your AC breakdown should be about as follows, for 52-54 AC before expertise, with a maximum of 60 when you press the turtling button:
AC
Base 10
Dex 4
Armor 8
Shield 6
Tumble 6
Song 6
Bark 4
Mage Armor 1
Boot 1
Haste 4
Helmet/Sheild Spell 2-4
IE 10
Total 62-64
If you do all these things, you'll have picked up enough constitution to let you hit the +12 buff cap, which should yield +180 HP. You'll also have mid-50s AC for most fight situations, and the ability to go to mid 60s at need.
Between these two things, and picking up 5-7 points of universal saving throws and additional spellcraft, you will be much more resilient against spells that have saves, and melee damage.