When you barrel TP, the value gets thinner by the street, esp if the board runs bad, so your bet-sizing should reflect the increasing thinness. Something like 75%, 65%, and 50% is pretty standard, possibly even smaller on really bad boards. But these bets are always bet/fold on the turn and river.

The turn 9 isn't that bad a card because alot of his worse one pair hands just picked up gutshot equity and so will def call another street even though they're way behind. The river Q is a bad card because alot of the hands you were getting value from were Qx and of course they just got there. When a passive villain donk shoves here, I think you're almost always beat.