Eh, this seems a little nitpicky to be honest.
Of course hot-keys will be limited on an XBox, it's a controller and not a keyboard. That being said, I don't think they implemented the switch in an effective way, but it's not too terrible. To say you only have 4 active skills is a lie though, set up one skill-set with buffs and the other with your damaging abilities. I simply switch for my buffs when needed, it's not that bad.
Splitting stacks would be nice and would have been fairly easy to implement when porting over to XBLA, but it's not game-breaking. Maybe using RB or LB to initiate the stack split, then up/down on the analog to confirm how many to split. Still, not the worst thing ever.
Using your pet to pick up items on the ground that you don't necessarily want clogging your inventory sounds awesome, I wasn't aware that PC had that option since I have only played it on XBLA. That would save precious time from me swapping all the useless items over to the pet. Nice quality of life improvement, unfortunately it seems like it'd be quite challenging to incorporate. Either way, it's pretty simple to run over loot and spam the "A" button, and it picks items up really quickly. Just requires some sifting through to swap things to the pet.
Standing still while attacking isn't possible, but the alternative is just slightly moving the analog towards the enemy and seeing the enemy light up red signifying that it's targeted. You'll move a tiny bit, and I won't know how useful it is until the I start playing a ranged class.
The spell system could be better, I haven't really thought much about it though since I've only used one spell so far anyways, the rest are my class abilities. This may obviously change at higher difficulty levels.
@Wolfie the manual is going into "Option" and "Controller Settings" and looking at what all the buttons do. Seriously, how would any controls be hard to pick up? You have LT, RT, Y, B for skills, LB, RB for mana/health potions, "A" interact button, "X" regular attack button, and D-Pad UP, D-pad DOWN to switch skill sets. It doesn't take a rocket scientist.
It just seems like you guys are picking the smallest problems and ignoring the big glaring ones, like pet AI being terrible and ranged attacks being challenging to pull off & aim. I care less about splitting potion stacks and more about my pet following me rather than running into a wall at the top of the stair case while I kill the entire floor.