Well this game is definitly on my christams wish list, and if I don't get it I'll have to buy it myself. But as I have only played the demo I don't know if these have been fixed in the full game but:
1) the ability to assing bots to deploy turrets.
2) the ability to set order for the attacking bots during the deployment phase.
3) I like the hud in non-gunner mode, but the hud in gunner mode could stand some improvements.
4) a button assinment to toggle gunner and movement to on off instead of holding down a button.
5) the ability to lock a range on a target so that if you move of target to lead the shot the range won't change.
6) the abilty to assing the mouse wheel to things, such as manual ranging, zoom or even to set the throtle on a vehicle so there are more options besides full speed and coasting, this might help with 7.
7) some vehicles are a little to top heavy and fall over too easily.