I’m a superbacker and I’ve slowed down a fair bit (I say with 3 campaigns still in queue, I CAN QUIT ANYTIME).

I don’t know about highest spends with least plays (a number are tied in the 40-50 range). I don’t go in whole hog unless I know I’ll play the shit out of a game, and so far the ones I’ve backed high level I either got my money’s worth long before the KS started, or since. If I had to judge it’d probably be something in the mid tier – for me it’s probably Fate Core or 7th Sea. I love the Evil Hat guys to bits, but Fate is so not my jam. Similar scenario with 7th sea. I loved to read the books (and they’re super pretty, great reference material, and well laid out) but … yeah.