How does it feel?
While, of course there are other classes do damage with mana, hunters are the only class where it doesn't really make sense. Enhancement shamans and retribution paladins, for example, still have a sense that they are casting spells when they use mana, while hunters need mana for shooting poisoned arrows and laying down traps -- activities which (aside from Arcane Shot) should logically require more technical know-how than arcane energy. It would make more sense for a hunter to prepare traps and arrows ahead of time much like a rogue prepares poisons, or at least to spend some other sort of non-magical energy on them -- but that, of course, would make the class feel very differently, wouldn't it? Could we argue that some sort of change to the mana system for hunters would make things better? Or, on the other hand, if the mana system ain't broke, should we really even think about fixing it, regardless of how "illogical" it might feel? Heaven knows there are all sorts of illogical things about the game and class mechanics already.
And yet this issue isn't really about logical realism so much as it is about look and feel. It's a different kind of logical sense that says hunters shouldn't use mana -- not like a voice saying, "But hunters wouldn't use mana in real life!" so much as a nagging feeling that mana doesn't feel very hunterly. It's as if a mage could walk around with a massive two-handed axe, or death knights could inscribe their unholy runes on a fishing pole. It doesn't really feel like something your class would do.
Naturally, of course, however it feels, that's just exactly what our class is doing as we speak. The game says that hunters use mana now -- and you could easily make the argument that it ain't worth the trouble to go about changing the mana system for something else with hunters. Indeed, such a change might cause more problems than it solves.
Know them limits
But what are the problems hunters have with mana, other than just that feeling some of us have that it doesn't "feel right?" Hunters complain that they run out of mana too soon, in long fights, or that we have to give up our attack bonuses (such as Aspect of the Hawk) in order to get more longevity out of our mana pool. In truth, however, this kind of tradeoff seems like one of the intentional choices Blizzard has built into the hunter class -- short bursts of lots of ranged damage, or more sustainable damage over a longer period of time. Some hunters may not enjoy making the choice, but as a game mechanism, it's actually a pretty good one. All the power mechanisms for special abilities in the game have limitations that nobody likes. Mana users hate running out of mana, of course, but warriors hate the feeling that they can't build up rage fast enough sometimes, and rogues hate having to wait for energy to replenish before they can get off their finishing moves. No matter what power mechanism you have, there will always be some limiting factor involved -- if it isn't the particular set of limitations you have now, then it would be something else, perhaps even worse from the current complainers' point of view. You can do some of the damage all of the time, or all of the damage some of the time, but you can't do all of the damage all of the time.
A friend of mine that was around when WoW was still in early early beta claims that hunters used to have some kind of aiming bar, which allowed us to use our abilities depending on how long we had been standing still, "taking aim." (Can any readers back this up, perhaps?) Apparently, this was back before we even had pets, so who knows -- and obviously, however this idea might have worked at first, it got tanked pretty quickly. Hunters are much more fun when they're able to move around a lot -- in fact moving around quickly and using all the space you've got is one of the most interesting things about being a hunter, and with abilities like Steady Shot, standing still does have its perks in many situations.
So other than the feeling that mana doesn't quite fit the hunter class, and aside from the untenable complaint that hunter limitations aren't fair for some reason, the only real problem I see with hunters and mana is that it forces us to take account of our intellect when choosing our gear. To be honest, however, abilities like Aspect of the Viper go a long way, in my experience, to help counterbalance a relatively small mana pool, and I don't mind using mana potions just like mages do. To me, mana potions feel more useful than either thistle tea for rogues or rage potions for warriors. Shot for shot, it just seems that we can get a lot more use out of them, and they feel a lot easier to get a hold of too.
So here I am, having said all this, basically convincing myself that it's better to keep the mana system than to try and switch it out for something else -- and I find myself a little bit saddened by this realization. The feeling that mana just isn't hunter-like doesn't exactly make me cry myself to sleep every night, but it persists. It floats up to the top of my mind every now and then and wiggles about. I look on jealously as death knights get not one, but two different power bars underneath their character portraits -- one bar for runes and one for "runic power" -- it just doesn't seem fair! I want a special bar and nifty combos too! Death knights are cool and all, but in my heart I want hunters to be cooler! If Blizzard announced today that Wrath of the Lich King will replace hunters' mana with rainbow-colored Pew-Pew-Powa, I would smile and read on about it eagerly before admitting to myself or anyone else that it may not be such a good idea.
I guess I'll just have to mark this little desire (or is it just envy?) for special hunta-powa as one of those "Oh wells" in life. Yeah, it would have been nice if it could have been possible, but alas, the rules aren't likely to get changed this late in the game. I think I'll just pretend that hunter mana isn't so much magical energy as it is a rough measure of cunning and preparation in battle, and I'll suggest any other hunter who doesn't like mana-usage do the same.