I've been watching the discussion about Brutallis, the second boss in Sunwell, and the first real gear check in The Burning Crusade. One thing that has jumped out at me is the side discussion about Leatherworking drums. Drums are items which can only be used by leatherworkers, but provide a temporary buff to the group. Apparently they are quite powerful, and are pushing people to do things like stack the raid with leatherworkers or change professions.
Drums are just the latest consumable to have issues. Flasks and elixirs got sorted into the Battle/Guardian system to keep them under control. There are complaints that the caster classes have to chain mana potions every two minutes.
So it begs the question: Are consumables--items which give a temporary bonus and are then destroyed--inherently bad design?
In theory, potions and flasks are pretty cool. They're a strong part of fantasy literature, and the idea of brewing elixirs is pretty neat.
But in practice, consumables tend to be annoying. Because they are powerful, content tends to be balanced with the expectation that the players are using them. If content wasn't balanced around that, a buffed group would find it too easy. As well, farming materials or money for consumables is something you have to do for every raid. Basically, you're continously expending a lot of effort just to stay level.
Permanent items on the other hand, like armor, enchants, and gems have a large initial cost, but once you meet that cost you're set. You've actually achieved something, and your character will always be better from that point. To me, gathering the materials for a [Red Belt of Battle] seems much more worthwhile, and much more fun, than gathering the materials for flasks for the next week of raiding.
Of course, WoW can't remove consumables entirely, as the Alchemy profession is based on them. But it might be a good idea for a new game to simply not include consumables. Make buffs either permanent or easily renewable. In many ways, I think the endgame would be a better place if consumables didn't exist.