An appropriate spot for a bluff?

Full Tilt Poker $0.25/$0.50 No Limit Hold'em - 9 players
The DeucesCracked.com Hand History Converter

CO: $25.25
Hero (BTN): $52.30
SB: $15.50
BB: $17.50
UTG: $58.80 - At the time, I had all of 14 hands on him, but he seems to be a spewey, LAGgy player. He turns out to be a 38/9 / .9AF @ 70 hands...
UTG+1: $22.35
UTG+2: $76.65
MP1: $17.50
MP2: $67.25

Pre Flop: ($0.75) Hero is BTN with 9s As
UTG calls $0.50, 5 folds, Hero raises to $2, 2 folds, UTG calls $1.50
I isolate the LAG, in position.

Flop: ($4.75) 5s 6h Th (2 players)
UTG checks, Hero requests TIME, Hero bets $3, UTG calls $3

Turn: ($10.75) 2h (2 players)
UTG checks, Hero checks

River: ($10.75) Qh (2 players)
UTG bets $10.75, Hero raises to $30, UTG requests TIME, UTG folds

Final Pot: $32.25
Hero wins $30.65
(Rake: $1.60)

Here's my thought process: We check through the turn, which is likely bad for the both of us. I don't think there are many flushes in his range that he's not leading on the turn, given my "weak"-ish flop lead (i.e. there's not much I can rep on this board, save for an overpair, which is less likely in the BTN position given the iso raise). Regardless, there are plenty of overcards to the board that I can hold, given the nature of the Ten high flop and deuce turn, but the obvious 3-flush freezes me up. When he leads full pot on the river, it just seems like such an obvious "please fold" bet, that I have to raise to a price that hurts. I thought about the min raise, but considered that it would be too easy for him to look me up with a call. Therefore, I go with the 3x raise, a bit more pricey call to make with any heart Queen down. If he has half of a brain, which he clearly did (and he did not easily lay his hand down), he knows that he can only make the call with the Ah or Kh.

P.S. I was thinking about the formulaic aspect of this hand; [30 / (30 + 10.75 + 10.75) = 58%], meaning I need this to work 58% of the time for me to show a profit. From a math perspective, I think a raise to ~$25 makes this a ~50/50 prop for needing to be successful, but I think the chance of success drops dramatically with the reduced call size.

FWIW, take the bet size and divide it by the current pot + the bet size to determine the percentage of time needed for your play to be profitable.