hand 1
I think it's fine

hand 2 - what hand range do you think he has? I probably lead river bigger, he hasn't shown any strength and I expect another call unless you've watched him slowplay to the river before

hand 3 this line is fine, but I'm betting you got a fold on the river? I'd rather lead flop to make the pot bigger on an earlier street in case he either checks behind or reraises. If called, I lead turn again. If r/r on flop I check to him and r/r turn

The turn card didn't change much and neither did the river, I would put out another $16 for a better value