It seems like a big sacrifice in convenience to have skills like loremaster and bartering and lucky charm only work for one character just so that player that invested in it feels special. Especially in solo play, where that doesn't matter. Make allies have to be somewhat near the loremaster/bartering member, fine, but party wide benefits would mean a lot less shuffling items and characters around. There's limits to how much skills should be shared -- persuasion and pickpocketing shouldn't be shareable, for example. But in cases where it's mostly a matter of a convenience, some sharing would help speed things up. Given a major criticism of D:OS1 was all the tedious micromanaging, Larian ought to eliminate all unnecessary clicks.
