Much like Divinity OS2 I suspect this will be one of the first things modded if it's not in the official game. You already have two additional characters added to your party during the first rescue mission so it's entirely possible if a bit unbalancing.
I prefer 4 myself. The way this campaign is set up, 6 would be overkill.
-Glimpse
I think the EA version's combat is balanced based on 4-member party. But why not 6? I would really enjoy more options to choice during combat.
But, for a 6-member party, entire battles -including a random battle on the world map- should be rebalanced IMO. The number of enemies per combat and the average level of enemies and combination of enemy types etc...
With a 6-member party, the current EA content will be too easy. All combats will be over within the first or not longer than the second turn. As a person who doesn't like alphastrike meta, difficulty and level design should be managed based on the level and number of the player party.
I'm accustomed to the 6 member party system and really like it but understand the balance issues adding this might introduce. They have also obviously put time and resources in to fully voice acting all 4 characters. Adding another 1 or 2 might not be so simple for a small dev team. Although if they were going to go for it now may be the better time. I don't know how much more content they have completed but adding in the changes required to boost the part size now would be easier than doing it after they have the entire campaign completed.
If they can do it I think 5 would be a nice number. It's that one flex slot that could make things a lot more tactically viable and interesting. I find right now that with 4 everyone but my mage tends to end up in melee combat, sometimes my mage too. Very difficult to build a dedicated archer which is what I was trying to go for in my playthrough.
I think the EA version's combat is balanced based on 4-member party. But why not 6? I would really enjoy more options to choice during combat.
But, for a 6-member party, entire battles -including a random battle on the world map- should be rebalanced IMO. The number of enemies per combat and the average level of enemies and combination of enemy types etc...
With a 6-member party, the current EA content will be too easy. All combats will be over within the first or not longer than the second turn. As a person who doesn't like alphastrike meta, difficulty and level design should be managed based on the level and number of the player party.
One envisionable solution : distribute the xp according to the size of party. (Small size = faster lvl up)