[beset7]

Against LAGs i bluff-raise the river about 15-20% of the time after a turn check like this. Firing again on the turn is an option but thats more art then science. If he decided it was worth calling the flop ace-no kicker or middle pair then he is probably calling the turn. I usually play it the same way you did but this is a spot, giving the preflop 3-bet where you could make a move on the river.