I sometimes just complete preflop because there isn't much problem swelling a pot against this type of player if we hit big, we can keep the pot small with marginal holdings and his preflop call still doesn't tell us much.

I checkfold the flop, value bet the turn if he checked behind and check call a blank river.

How long did he take before firing out his river bet? Based on previous info I call, he doesn't do this enough with a Q or pair, he knows enough to see you're weak and therefore a smaller bet on the river would worry me more.