Hand1. I muck KQo even in MP most of the time, I prefer to raise in on CO and OTB. Postflop is fine.
Hand2. I would fold to this flop bet often against a shorty. (TPTK or TPGK is the way to play with them.)
Hand3. Standard. Sometimes (rarely) I check it back against a loose shorty.
Hand4. I would minraise turn sometimes in this spot to go to showdown cheaply. All-in-all read dependent.
Hand5. Fine as played, though I check flop sometimes here.
Hand6. It seems that you are running bad to post this hand.

Edit: I've read Roy's comments. 4BB+1BB for a limper is a good rule in FR.
In 6 max I prefer smaller raises. I open raise 3,5BB, 4BB if there is a limper, 5 BB if there is 2 limpers if l am in position. OOP (i.e. SB, BB) I raise like 5BB+1BB for a limper. Though I think it all depends on the style you play and your opposition.