Party size! I totally agree. It's one of my main two concerns.
It doesn't feel like to much of a problem for most, i'd guess. But although i love divinity original sin 1 and 2, the party size maxed to 4 has always been one of the reasons i prefered baldur's gate (yes, there are other reasons, yet some things are better in divinity, ofc, it's not all simple).
It is very important, i recon. It multiplies the strategical choices and possibilities. I often find fights look very similiar from one another in DOS, whyle they are all so different in baldur's gate (and yes, i know how hard this sound, and yet i strongly feel it).
The other point i'm worried about is action points. I really liked the AP system in DOS 1. I really disliked the one in DOS 2. Les AP = less choices, possibilities, and therefore, more turns that are all the same, more fights that are all the same, and so on. Just because from all the very many options you get, it's often the same one that will work best. Seeing you only get one action per turn, period, in BG3, worries me. And yet i don't want to judge it in advance, as i might be better than the ap system of DOS 2. I'm just worried cause i don't know yet, i might be brilliant, or not. Looking forward to test it (cause i will, ofc).
But no matter what, larian, keep up the good work. What you achieve is amazing every single time, and perfection should never be a goal to anyone, so be sure that my critisism are not given through hate, but through love! <3