Imma add my 2 cents to this conversation and say no, stick with 4. MAYBE 5, but thats absolutely it.
All this nonsense that players are saying about conversations should be with everyone involved, huge parties, and what have you. This is 2020, games are no longer easy, or handed to you. You have to actually -PLAY- them, and that means making, (everyone duck!), decisions!
If you actually read other comments like the second before yours I've voiced, as a D&D player and sometimes DM that having more characters doesn't make the game "free" as you'd like to state or easier, it's just a matter of balancing encounters. By the way having more characters in a party if you do play D&D means, in basic words, that your encounters can be harder and have more legendary and epic monsters, specially in the end game which is where Larian needs to plan it really well right now.
BG2 actually made the top 10 games of all time due to the insane level of awesomeness they throwed at us, who can forget the first time they encountered the mind flayers, the dragons, beholders liches and other bhaal spawns? BG3 has to rise to the same level in the end (even if we need to take ir to BG4) . Those encounters were hard as f* even if you had 2 multiclassed Clerics and a Wizard and a Rogue and Misc.
yeah anyone who thinks video games these days are harder and that "old video games where easy" is full of themselves. I've been playing video games since the 90s. they've gotten a LOT easier