it might be too thin..

I'm expecting players here to always donk shove on the river with a flush and to check back the rest of their range to either c-c or c-f. While I don't think they ever have a flush after their river check, I don't think we can get value from too much.

If villan was a huge whale then I'd go for a small value bet to get called by Jx, but usually checking back.

Are there more hands in his range that you beat that he can call ? qk and flush got there but, there are still alot of 2 pair combos that can call a bet and if he is bad enough he can call with top pair, so i would bet 50% and fold to a raise, it might seem thin but there are alot of worse hands that can still call, so there is value IMO

(Edit qk was already a straight so its even less likely he has that and you are only worried about flushes for the most part)

i think if you had top 2 pair it would be more of a close spot but with a set i think he can call with alot more combos i would maybe go for thin value with top 2 or better and check anything else but i would bet 50% so that worse 2 pairs are getting the correct price

Given the fact that villain went for a bet/call on the flop and failed to lead on the river I think you can discount a solid number of monsters from his range and therefore I'm a fan of thin value betting the river.