Magnetic peg is a great idea!!! I like the idea of upgrading the pegs themselves instead of a split peg % chance too. We talked about this and went with %, but maybe we focus more on upgrading pegs and buckets and balls. It would be a lot of fun.
I agree that there's a huuuuge lull in the early/middle of the game, with few upgrades and not a lot changing. I'm hoping to rebalance this with our next build. Stay tuned :) And thank you for the great feedback.