+1 to cbet flop about 1.4.
As played, I think you can c/c the turn and pretty much check/re-eval any river. He may be betting the turn with just about anything (two pairs, set, straight, 99-KK, draw or complete air). A lot of his range is just as worried as you are about a straight card or a flush card.
I'd make the 4b pre a little bigger oop. I also would say it's a decent spot to flat the 3b oop if you ever do so.
Now post the river card and let's see...