Balancing out the fantasy base set with Pathfinder, Conan and Legends

[Miss_Musket]

Hi everyone! I'm a relatively new player who played for the first time at New Years, and bought my first set about a month ago (I have Booty, the base game with no expansions, and I've order Game Changers).

I'm planning on getting a lot of munchkin sets in the long run, they are so fun, and my four housemates love it too!

I have heard however that after the 2nd or 3rd expansion, the base game gets a little overbalanced, with the players being much higher levels than the monsters. I've heard about numerous ways to counter this, including playing with a few expansions at a time, removing the GUAL cards, and by mixing in the monster booster cards and the Conan base set.

I was wondering if, theoretically, you had the pathfinder, legends and Conan set, if you would be able to create 3 or 4 functional and balanced sets. For example, maybe splitting the steed cards between all the decks, but just have the centaurs in one, so their 'leader of the herd' power can never be too OP. Maybe work it out so that each deck has, at maximum, three or four races/classes/heritages etc, so it wouldn't be too difficult to find usable items.
After some play-testing, fairy dust could be added to the deck which is the 'hardest', and munchkinomicon can go into the 'easiest'.

I want to hear your ideas on this- I've not got first hand experience of anything other than booty and the vanilla game, and everything I've looked at doing is based on theory and what I've learnt from the munchkin subreddit (which is pretty dead) and on here.

Basically, my thinking was that if the game is pretty balanced with 2-3 expansions, and there are four fantasy base sets and eight expansions, jiggle it around a bit so that each 'base set' has about two expansions worth of cards each. Obviously sorted so that the elements that carry over in each expansion are utilised together.. I hope I make sense!