Not even sure about the C-bet size but might be ok?

I think it's probably ok, but my guess is a larger bet has more EV if you're choosing one size. It's close because villain has a lot of queens and jacks in range

At the turn once I got xr I'm also not sure about retaking the lead.

I would say checking range includes top pair, broadway flush draws, sets, combo draws, TP+FD, etc.

At 25NL I think you have a lot of stuff to bet into for value and very few things are going to check raise you twice, none of which will lose to you.

And the river: I feel like it's definitly too thin.

It's thin, and gutsy. In your favor you counterfeit top two pair, but against that you suggest there's really only likely two combos. KTs may find a call (two combos if they're in range, but way less likely), AQ hard to say but probably should lean fold, AK with a spade is in range because of how small turn bet is as is possibly AsKs, and maybe even AK. These are the hands you're targeting and there's only a couple combos after the check raise. I'd say optimistically more than a handful of combos and pessimistically like two

Against that are the sandbags and 9t/AT all of which are around at some frequency. That's a lot more combos.

I think I prefer a check.

This board and runout is horrible vs both merged and polar flop raising ranges.

Feels thin, I would check and go for it on better rivers.

nh, either AA or AK are your min value bets here but the distinction is important because AK is a ton of combos so you'd need to add a lot of bluffs which are hard to find. I think the strat of jam AA+ is good and dig deep for bluffs; for example if you ever bet TT on the turn just always shove river, that kind of thing.