So, being a major AI buff, AI is of course the first thing I think of. I'm wondering where exactly the AI of Voxel Quest is planned to fall.
1. They are allowed to do very little so as to keep them from doing anything stupid, but their final decisions are random.
2. Follows simple if/then/else statements.
3. Follows simple if/then/else statements, but is smart enough to remember locations, danger zones, things that are bad ideas, good ideas, things that provide good outcomes, etc.
4. Weighs multiple factors when making decisions rather than if/then/else statements - for example, "low on health, almost out of items, I'm far from town, friendly party nearby, so I'll rest instead of using my last health potions" instead of "I'm low on health, so I'll use my health potions or go to town"
There's also the question of, "Will the AI be able to teach itself, or will it all be pre-programmed by hand?"
Obviously the majority of this applies primarily to combat situations, but it can work in other areas too: For instance, having the AI remember that they were attacked and forced to flee when they crossed a certain mountain pass, or that Godherb Sunflowers grow on a particular overhang to the south of Feldspar Inn. Other instances might be their handling of other NPCs and the player character, determining whether they feel they can "trust" that player - or whether or not they're willing to take on a deal, etc.
Story elements might be a bit more difficult to maintain with complex AI - although that could be handled as well by simple personality traits, like Josh Parnell's ACEGILS model: Agressiveness, Creativity, Exploration, Greed, Intelligence, Lawlessness, Socialization. That would add a decent level of complexity to the mix, and would feel gamey... if that information was made readily available to the player. If personalities were included in such a way, it would be pretty enjoyable (in my opinion) to learn about the personalities of the people you're with. On the other hand, that's a heck of a lot of dialogue work to deal with.
Then there's the question of, "will the AI all be pre-programmed, or will it be capable of teaching itself?" I'm a major fan of self-taught AI (no, not like Terminator), though it can be difficult to implement if you don't do it right. There's more thought involved, but it would have a better outcome in the end. This sort of thing works like this: "I've learned through trial and error that using my sword while the enemy is protected by warding magic isn't a good idea," or, "Stepping on fire runes hurts a bit, so I'm not doing that anymore".
Anyway, obviously AI is a pretty big thing for me... :P Hopefully this post made some degree of sense, and I'm interested to hear everyone else's thoughts on it.