I have some ideas that I might try to phase in, but I also don’t want to mess with a winning formula too much.

That sounds very familiar. Usually the way which allows you to earn more is to move up in stakes and that usually comes with a smaller edge and more variance. I also assume that isn't really possible in local live Poker Tournaments. Your current win rate looks pretty nice and realistic though, while it might sound quite bad, why not settle for it trying to make tiny improvements along the way that don't carry the risks of messing up the winning formula.

Good luck, the fact that you keep close track of the numbers already puts you ahead of 95%. It is where it all starts and were most fail before they even begin.