you can always play with fewer characters if you want to unite more, speed up combat more and so on more. Maybe 2 teams of 3 united in one?
I generally like the idea though of argueing which number is the one true number
I also have such an idea to remove the limit on the number of companions. It's realistic! The main character and his twelve friends. Then everyone will be happy.
Studies with anectdotal sample sizes show that balance is fine up until you reach 27 party members.
Also it appears that this configuration adds the left side of Baldur's Gate back into the game. Larian thought of everything
On a side note, this is actually not that cumbersome to control and having a train of so many goons works and looks great. wouldn't work this easily with a non-larian-chained approach.