Pre is a standard 3 bet from me.

On the flop I think I don't mind the check, even giving a potential free card to Jx 7x. I'm really not happy about continuing OOP if we c bet and get raised.

On the turn I would bluff catch. it's difficult for him to rep QJ 7x here because I'd expect a 23/17 to bet the flop a decent % with any draws or showdown value once we check on this board.

The river bet looks like it's saying straight or air. Micro stakes players usually don't bluff enough to be able to call these off profitably, but I wouldn't hate it if you paid this off. I'm probably folding myself though.

I think I still like to just cbet this given the preflop positions, but as played I'd go for the same line on turn and river (assuming you folded).

You can cbet flop. While it looks terrible and should hit villain really hard, most players in your position will have QJs, 88+ in their 3betting ranges so it's definitely a flop you want to be cbetting at a decent frequency. This hand could be included in a strategy that cbets most nuts, some stronger overpair/TP type hands and bluffs. That being said I really don't feel that strongly about it so checking is fine by me.

Turn is 100% standard.

I find these river spots difficult. I do think villain can have more 7x than you initially give him. A7s 97s 75s, while on the looser end are definitely hands some villains will show up with. I would probably fold river to the 2nd bet and if you have hands like 87s, 77 in your 3betting range it's probably important to play at least some of them like this to prevent yourself from folding 100% on the river.

I agree with @Komododragonjesus about this being a tricky spot!

Out of interest, do you guys read into villains weakish bet sizing on the turn at all?

Pre: I like the three bet here for sure.

Flop: I would probably opt to c-bet here myself despite the uglyness of the board but the check call seems reasonable as well, once we are not planning on check folding then I'm happy enough.

Turn: Once we check flop then calling here is mandatory, folding would be far too weak IMO.

River: River sucks hard. My biggest concern here is that are hand is pretty capped and we are going to be showing up with a single pair and absolute ton the way we have played this and if villain is is any way good he will recognise this and can be piling on the pressure regardless of his holding. His check back on the flop would indicate he likely has some showdown value, but the problem is that a ton of his 7x here will have a pair to go along with the draw so his line would make total sense. I probably would click fold without any info as to how competent the player is but I am definitely not happy about it.