So I finally have all 160 Star and Moon Coins in the game, thank goodness.
It's such an ordeal, so many of the Ring Master + Star/Moon Coin Challenges are just downright cheap and require fluke luck or mulligan abuse, I can't believe I withstood all that.
The challenges outside of those (bar Sparkling Waters; screw the entire course) were such refreshing breaks that I always wanted to last longer, so I tried doing the RM + S/MCC ones first and it worked fairly well.
And somehow I left with my sanity, but I don't recommend doing the same as me, or if you do, at most stop at 100 Moon Coins so you get everything and don't suffer longer.