Hi, I am also in favour of having a maximum of 6 party members.
As many people have already argued here, using the argument that it slows down the game is silly. What slows down the game is the fact that they turned this into a turn based game (I think it's a horrible approach, but not gonna get into that here). The combat is already incredibly slow and dull with a 4 man party. And guess what... It's even slower and duller the more you reduce the party size because you have to wait longer and longer for the enemies to finish whatever they're doing before you can play again. So, if the issue at hand was merely the fact that it would "slow down the game", it would in fact improve it in every way as you can dispose of enemies faster, have more synergies and most important of all, you can actually play more often during combat.
Using balance as an argument is pretty uninformed (I guess it's the best way to put it without using other less cordial terms). Balance is something for the developers to worry about. We as early access players giving feedback are pretty much a sweat-shop QA team. Our job as individuals who want to better the game is give the suggestions we feel would do exactly that. We are not here to babysit them and say "oh, but the poor lonely devs already have other Jira cards open in their dashboard... let's not give them more work". That's... stupid. A 6 man party would better the game for a great variety of reasons which have already been stated here, so if you're gonna argue, use arguments that actually have an impact in the GAMEPLAY AND THE PLAYERS, not the developers. This is their job, they are paid to do it, and you pay for the end product. Not to mention that balancing in this area of party members has been done for many years successfully. As anyone who's played the original Baldur's Gates can tell you, and they are over 20 years old.
With these issues aside, I feel the biggest problem with having a 4 man party as a maximum is that it is extremely restrictive to the player. Most people will want to have a balanced party. I don't care if you can make Gale into a swiss-army man and have him lockpick, disarm traps, charge a boss on a flaming unicorn wielding a staff and magic missiles. To me this just seems like I'm playing DOS 2 again, where every character does everything. This just removes uniqueness from your companions and the idea of roles (which I feel most people who enjoy DnD games like) kinda goes out the window. DnD games are amazing for many reasons and party management is one of them. 4 man means you're locked into a core that you can't really change without gimping yourself in effectiveness and/or fun. You'll most likely want a front liner to deal melee damage and/or tank (say a fighter), a support which can buff, heal, disable (e.g. cleric or druid), someone with utility for exploring, scouting, lockpicking, disarming traps, etc. (like a rogue) and a spell caster. Sure you have a party that can finish the game but you have no room for imagination or fun.
Also, regarding the mods argument: Sure, eventually modders can make a mod for the party to have a maximum of 6 members if Larian does nothing about this, but it is much better to have the actual people who are developing the game and have the insight and ability to fine tune it and balance it properly to do so as it would no doubt lead to a much better experience for everyone.
