Again it's my opinion but i think that would make big difference:
1. Colors - many people see the colors in BG3 and instantly compare to DOS2, but it's true, and i think it's because of so much similarities with light green, too bright. if you look at BG1 the colors were definitely darker green
I love the BG series but it is a very
brown series. I welcome the variety of colors.
2. Party control - i think in old BGs had it right, click on portrait that avatar was selected, select 2 or 3 use mouse, select all you get the idea. this chaining HAS TO GO, i spent yesterday most of the day playing, my wrist hurts now. and if you say it worked in DOS (not really) and that's precisely why it shouldn't be here.
The F-keys can select your characters.