The biggest I’ve gone is to play with two 24-point forces on each side (pretty close to 50 points). We had the 2 forces on each side under their own commanders (so 2 in each army), to keep things moving if a failed command test stopped a force early in that side’s turn (still not an antidote to both forces failing early, though). I think it’s important to do something like that, or tweak the rules around having the player’s turn end on a failed activation- it’s too easy to have command paralysis hit big forces, otherwise.