I don't have a lot to add since the general consensus is pretty close to how I feel about it and I see it's already on Larian's radar, but I still wanted to give my vote and say that I'd like fully shared xp as well.
I play these games exclusively with friends so it's never desirable for us to want personal quest rewards, even (or especially) for situations where one of us kills an enemy while away from the party. It's a little cumbersome having to call for everyone to join you before you finish off a trivial mob or turn in a quest to make sure they don't miss out on the xp.
