I know how you feel. One of my issues with the game ( as much as I absolutely love it ) is I have restarted 5 times trying to settle on the right difficulty and mods vs no mods. I played the 6 man up to getting back on lady vengeance and it seemed quite stable ( with some minor UI and dialogue shortcomings ). I tried it on tactician.
It was definitely getting too easy quick, and that is no surprise.
Then I tried it with a 5 man party and that was almost right.
In the end I have settled on restarting on tactician with 4-man but I use a few cheats. Nothing big but I like rounding out my stats so all my guys have more armor flexibility, and a free pet pal and a couple other skill and talent adds.
But yeah...there's no way around it getting too easy with 6 in party I think. 5-man might work for you though. But I just can't say if it is stable all the way to end game.
