This may be unanswerable, but at the tightest point, how much play would you expect to see from the resting place? Should it visibly hang (curve) as it sorta does on the loosest point? I'm thinking maybe I just have things too tight. It just seems like there's a big difference between the tightest and loosest.

Thinking about it now, the noise comes in half turns, so this would make sense. I'm kinda worried that giving it more slack will make the loose much too loose. Could centering the chainring solve that problem?