You're overthinking your nut advantage. Most players are not considering what it LOOKS like you have. Boards like this the guy either whiffed completely and is maaaaybe calling one time to keep you honest with something like 66, Q9, etc. Or he's just got 78s and is done with the hand. Flop bet is fine. Turn check is okay at this depth as you'll x/r AI for most sizings he takes, its a little face up though..maybe you'll check call stop and go. Once he checks back OTT its a small river value spot. He's got KX QX, he's not checking back an A OTT. You'll occasionally stack a 9. Bet river like 25 to induce.
I'll admit that after a few limps I might just see a flop here. Otherwise, I'd typically have to make it $25 to have a chance at thinning the field in my game, and I'm not really loving committing with this hand (which is admittedly my least favourite hand and there's an outside chance it is even my biggest losing hand, although I don't keep stats on that sorta thing).
Anyways, we got it HU for about 10% of our stack to an SPR of 4.5 so we're probably in commitment territory postflop OOP.
I think I might just check this flop. If any money goes in with us betting, we're most likely behind. If any money goes in with him betting, we're ahead some of the time. Anyhoo, that's my thought process here.
I'm fine with the turn check. Admittedly I have a very nitty image to deal with, but all but the most aggortard of players aren't getting paid off here by worse (especially by a competent player who won't be chasing 4 outers and is probably unlikely to have a backdoor flush draw, which they may turn into a semi-bluff anyways).
I probably bet the river. A competent player just isn't going to valuetown themselves enough here by betting thinly as it really looks like we're just trying to check down our showdown value. I bet small and hope that gets paid off or perhaps induces him to turn his showdownable hand into a bluff.
Hero indeed led out for 55 on the river, hoping to get called down by any 9, maybe a disbelieving 2-pair. Villain pretty quickly folded, which made me feel like I screwed this up.
I wondered if there was any worse hand he had that would have called, if there was any chance he'd interpret this as a bluff and call down light.
Maybe I would have been better off checking river and letting him to try bluff at it (basically, committing to the slowplay and the ruse that I was very uncomfortable with the 1-liner out there).
My guess is that it probably didn't matter too much (although I think our river bet was too chunky, I wouldn't have gone any more than $25). Bottom line is that it is hard to make money off of competent players OOP.
I think it depends on two things. How likely the villain is to bluff river, and how likely you are perceived to bluff river. If villain is likely to believe you have bluffs, I would bet. Previous suggestion to overbet pot is a bad idea in a low stakes game IMO. Overbetting is very rare in my experience in 1/2, 1/3. Unless this is a standard play for you as a bluff or this particular game had a good amount of that, no way a TAG will call an overbet in a 1/3 game. If he seems to bluff a decent amount, I would give him the chance.