Playing on Party, no specific read on villain

Call should be more than ok, 3betting makes no real sense to me

Prefer to check/call instead of donk because would not like to get raised with bottom2

After his check behind on flop I see myself way ahead vs mediocre hands like weak pairs or weak draws like a gutshot or combined. since I block some gutshot kombos with my A9 I weight towards the weak pairs. Now that he calls I might also play against some flushdraws

Now this is the street where I was totally clueless: given my reads on previous streets I think I should have a bit of showdown value. I block several straights, so my guess is I'm facing more weak pair kombos but much of them evolved to better 2pairs now. still left are busted flushdraws from the turn. I really see several options: check/fold as played but I might get bluffed of the better hand. Bet large and represent the straight(s). but that turns this hand into a bluff. question is if my showdown value is so small that this would be a good idea? All these thoughts get me thinking about another option: checkraising the river: On one hand I would be happy to see a showdown but if instead face a bet I will produce heavy FE by my checkraise so that I think I even get set of jacks to fold. How do you decide and why?