I was really unsure how to play this river.

I guess the flop plays straightforward, LLL boards UTG vs. BTN are range checks for me (especially multiway) and top pairs as well as overpairs go into my c/r range. I am also comfortably betting turn here, as I can extract value from all Ax draws, flush draws, and weaker overpairs 88-TT. Stronger overpairs would have 3bet pre and sets would have most likely raised the flop multiway.

The river is probably the worst card in the deck, completing the flush and giving all straight draws with Ax a better pair. My hand is not strong enough to bet, I did not want to pay off a large bet from Villain, and c/f just seemed to weak, so I went for a roughly 25% potsize blockbet. Well played? What's your approach on the river?