a couple of thoughts:

hand 1: i play it the same. it is very awkward as you said, but i think it's right. the turn bet looks awful when you get two calls, but you really expect one at most and in that case you will either have the best hand or plenty of outs to draw against a 5 or 9 or whatever.

hand 2: easy bet/fold on the river, as MP's most likely holding is a 7.

hand 3: i have no problem folding this turn vs. unknown.