Hand 1: Unless your opponent gives an absurd amount of post-flop action after limping, you don't want to play a big pot here. Re-raising the flop is setting money on fire.
Hand 2: Standard, I call with worse.
Hand 3: I would just bet the turn and either bet or check/call the river. So many worse hand call that turn.
Hand 4: Sometimes I check there pre-flop, depends on what I think of my opponents. I bet more monies on every street.
Hand 5: If you like the river call, it's fine.
Hand 6: Bet the turn, I hate the river without a known retard read.