I think if you bet 1.9 in hand 1 on the turn it's fine
probably checking it back is standard because even a loose player's river payoff range is not going to be more than 50% weaker than ours
the problem is that EVERY draw got there so a weak player will have those 78 or spades here a lot
a stronger player might be raising these draws on the flop, but it still sucks because now he's going to be afraid you made them

I think it's a bet/fold only against someone that seems like a fish