There's no reason cleric spells shouldn't or couldn't have similar reagents to cast, and remove piety altogether, or only have it apply to god saves.
So for clarification purposes since this got Top paged: [for ease you can replace Cleric with Druid and its still accurate]
Since I lack any documentation on 3.0 specifically, I'm pulling information from 3.5: Both wizards and Clerics require 1 hour in preparation/supplication to regain their allotment of spells following a good rest. That's it. Level 1 cleric/wizard Level 30 Cleric/wizard matters not. It takes 1 hour to either study your tome and memorize your spells, or supplicate before your deity and be granted your miracles.
Allowing Wizards to simply regain their allotment of spells by resting, and needing to only bring relatively cheap reagents to ensure they can cast them for extended periods of time, (as wizards can bring several hundred , if not thousands of components along with them) vs. Cleric's being limited by a maximum of 100%, and 7th, 8th, and 9th circle spells (and 10th for those epics) being 1%, 2%, 3%, and 5% respectively, this seriously tips the balance of power in favor of wizards for longevity purposes.
Their mechanics should be similar, and staying power equal. It makes zero mechanical or thematic sense for clerics or druids to have to abandon whatever they are doing to wander off somewhere, potentially far afield, to find an altar to pray at. It is a thing they should be able to do anywhere, at anytime.
With this in mind, I am advocating a reagent system like that for arcane casters for Divine, with reagents being as easily craftable and acquired as those for Arcane casters. With this done, piety could simply be a thing for god-saves.
I should clarify also, I do not have as extensive playtime with clerics as I do with my wizard so if the aforementioned problem isn't ACTUALLY a problem, then feel free to disregard the hell out of it.
