Oh, if I missed some previous posts and misunderstood your intentions I'm sorry. ... quick reading ... Yep, my fault. So we're on the same side.
I'm either/or for more or less characters really, there're benefits to both. I would hope for a few more than the 8 we'll probably get (maybe 12?) with a little less effort for each, mostly because I feel the characters in BG3 are overwritten - too much backstory/ too many opinions/ too much emoting etc. Puts me in the passive mode of absorbing rather than imagining which is my preference (to a point). I guess I feel like they're better TV characters than game ones? Idk, kind of besides the point.
I feel the Origin system is the root of most of this tbh. Everyone is a protagonist > everyone needs lots and lots of writing (too much for a side character, and often quantity over quality at this scale) > there can/ should only be a small number of them > party of 4.
If I were an executive: No Origin system (no one expected it here) > companions are complex side characters > there can be more now > party of 6.