The opener is fine. Certainly interesting to see how many callers you're getting and perhaps some adjusting is needed. However, I don't have any problem playing multi-pots. There is more to NLHE than isolating and c-betting.

The turn bet is really retarded and the river call is setting fire to your bankroll.

I don't like raising the flop because with pot vs effective stack size it's really hard to protect much of anything or figure out exactly what is playing back at you (made hand vs draw.) You can't put in a reasonable enough of a bet to protect while only reasonably getting called by worse hands. If they truely suck, then pushing might not be terrible.

I would just call this flop and check behind on the turn. The joy of these players is that their under-bets make this line really easy. Pony up the $4 and if the turn is a 2 drop the fucking hammer and cackle with glee as the fish have to think for several seconds realizing that their monster draw just TURNed into dogshit.