On the river here I think you need to bet small enough that Villain can talk themselves into a call with their Queens saying "I have to because pot odds". It has nothing to do with small bets being underbluffed and everything to do with the fact that one of the effects of nits playing so tight is that once they get something good enough to 3-bet, it just feels bad to fold it. The fact that half the Aces are out of the deck makes it less likely that he has one to call you with here, and the way this hand went down you are pretty much turning your hand face up when you bet the river. I get what you are trying to do by making the bet bigger to look more like what someone would bet here bluffing with air or some low PP but I think that repping that will be less effective than making a bet small enough that Villain can give themselves an excuse to see a showdown with their pair.

I agree that the bet on the river seems a bit too big. You are targeting KK-JJ to call you, and judging from your description above, I would assume they fold.

I think the turn check is fine. You will only get one street of value. On this board, there are not many draws villain can have that you would want to charge, and you dont need any protection. KK-JJ will call you or not regardless of the street, and you loose less should he have devided to slowplay his AA.

I think you're getting too tricky here, you just have a clear value bet on the turn and a shove on the river. When you x back a hand like this it's because you expect to see very aggressive play from villain on the river in response to your x but that's not likely to be the case so betting the turn is just going to have a much higher EV until you start coming up against some very strong villains.

Don't size the river smaller, if they never call just bluff tons, I honestly going any smaller here is a bit ridiculous and is honestly pretty weak tight.

Also if you think that the mistakes this person makes is that their turn x is super capped and will overfold massively to aggression the way to counter this is go into a solver, start finding some hands to float light that you can comfortably fold to double barrels but you can turn into bluffs on later streets when they take passive action. You can't exploit a player like this if you never show up with a hand to bluff.

I agree with Dengs. You called pre with AKo, got the best possible board and now are afraid to go for it, in your own analisys he can have AQo so why not put this hand into trouble?

Thanks for your comments:)

I think the turn bet makes more sense (just from the logical point of view)

Btw he called with KK