errr..
I'm not sure that would have the effect you desire, What exactly do you think a "campaign version" should do?
it'll probably make every difficulty about the same, but then what do I choose to balance to?
I play on very hard campaign difficulty so I'd probably balance towards that, causing every other difficulty to feel that way too, but are you looking for that, or are you looking for me to balance the game towards easy, normal, hard or legendary campaign difficulty instead?
and if so, what is the benefit over just picking that difficulty yourself sans-mod?
Not to mention the buffs AI gets in campaign aren't exactly as cut and dry as they are in battle
To be clear: I'm not saying I won't do it, I just need you to be very specific about what it is you are looking for here.