not a lot of news here.
the bit about advantage basically tells us nothing as long as we dont know how the game is actually going to play.
Inspiraiton i guess you could see a bit like Edge in shadowrun, only you can only have one of them.

basically you can, on any roll, drastically increase your chance for success. In DnD its up for the DM to hand out inspiraiton, i suppose in BG3 youll get it as a reward for.... good question what constitutes "good rolepalying" in a video game