An outsider's take on things:
What Voadam's system reminds me most of is a basic DKP system (Dragon Kill Points - an online gaming term that refers to a system designed to fairly and evenly distribute loot among a group of players). DKP is, by now, a proven system, having been in use for over a decade.
That said, it doesn't mesh well with expendable items. It works best when only considering "permanent" loot, because it tries to balance the advancement of the group as a whole. Using this example, once Col uses that elemental gem, that's it. It's gone, and all the cash he "spent" on it is gone as well - which leaves him, and thus the entire group, in a bad spot. That's just exacerbated by the fact that Archivists are one of the more expensive classes in the game to run, especially when you choose not to learn healing spells.
My opinion would be to either pool "permanent" (including raw cash) and "temporary" items into seperate pools, or to simply divvy up temporary items with a "Who wants this?" system, selling the item if it's unwanted for 'bonus' money.
[sblock=DKP sidenote]It's not exactly a DKP system because in general you can expect D&D parties to be less confrontational and competitive about loot issues than your typical MMO raid group. The mechanics are basically identical, but the goals and politics of the system are pretty different. YMMV on my commentary here.[/sblock]