Yeah I was thinking like determining a target amount of posts, and having the fees adjust to hit the target. Gonna use some simple numbers for sake of ease.

Imagine 100 posts under 'bitcoin' sub being the goal per day. Base fee to post today is 100sat but we get 250 posts instead (no post limit per day). The adjustment basically being base fee x (actual posts/desired posts). 100sat x 2.5 = 250sat to post.