1. Is a turn raise mostly to get value from worse made hands, because without raising somewhere I'm not getting allin? Or is it mostly to let draws pay? Any advice on betsizing of the raise?

My thoughts were with this heavily underrepping of my hand I can get more value from Jx-KK on the river.
The decision wether to keep weaker hands in for value on later streets, or bet/raise them out to get maximum value out of villains strongest made hands (which are still weaker then hero's hand) is actually an interesting subject.

3. Do you prefer b/f because if villains bets the river closer to pot, we can't call? What's your betsize on a b/f?

4. Assuming we call preflop, how often should we be c/r-ing low/paired/Jxx flops to make it profitable?
Why are we raising flop?
(the interesting topic (see comment hand 1) becomes more and more interesting, maybe I'll start a thread about it in a few days)

Also, if villain was i.e. 20/17, should I standard be 3-betting KQs?