Two things that really bothered me during the play through (aside from some camera issues).
The first is the pathing. The companions following your selected character at the wrong times happens soooo often! The group and ungroup option is way too much off a hasle. Something like a hold your movement and come to me command would solve a lot I reckon!
The second one is the inventory and equipment screen. I would prefer to have them in the same window where I can drag and drop my items freely between my characters and the inventory.