Since I'm taking a hiatus atm from WoW, I haven't played with the new spirit changes. However, I will say that Evo cooldown used to be 10 minutes. The first time it was lowered, I was like, "woot!" The second time, I was like, "Again? Okay... woot!" When I saw the talent to reduce it more (I've been arcane for 5 years) I thought, "wow... okay." Any further reduction that you propose just makes it way too much. You don't need Evo that often.
Charges for the mana gems, sure.
Higher water... Since you don't remember Evo being at 10 minutes, I will assume that you don't remember this:
http://www.youtube.com/watch?v=rvd5hpX2dy8 
There was also a long running joke back then that the next tier of mage shoulders should look like those water machine jugs. Oh- and there was a mod to aid mages (or raid leaders) in handing out food and water called... Vending Machine.
Soulbound would solve these issues, of course, as you've already stated. But then you'd get Pallies, Priests, etc. complaining that they can't use that water, so...