I feel like I broke the game beyond all comprehension... (in the best way)
In case you're wondering, I scaled to absolute insanity by taking every single "add 2 to prairie each time it scores" and "add stars to terrain" option I could to build the GIGAPRAIRIE. I also got lucky and collected some "if the size of this terrain is greater than X..." added on.
One tip to make these strategies less busted. Make reroll cost scale rapidly per round. I got to a point where I was racking up crazy amounts of money to the point that I could reroll and buy everything I wanted a dozen times, increasing my power level and chance of getting what I needed super quickly. I basically bought every prairie and prairie buff to the point I could guarantee they'd appear first draw every round.