Learning to read hands headsup

[Supwithbates]

I was playing my friend headsup (just as practice at handreading), and ran into this interesting hand.
Headsup tourney, blinds 1/2 (we each had about t75 in chips). Blinds were not slated to increase, as I felt they were about perfect as they were.

On the button, I looked down at J[img]/images/graemlins/diamond.gif[/img]5[img]/images/graemlins/heart.gif[/img]. Not a very strong hand, so I decided to limp. Villian looked down at his cards and immediately raised to 3 BB. As he'd recently been aggressive, I decided to call again with position as I'd been giving his raises a lot of respect recently, and I felt that if he was holding a marginal hand (he'd raised the last 4 times I'd limped), he might slow down and I'd be able to take the pot away on the flop.

Flop:
A[img]/images/graemlins/heart.gif[/img] 3[img]/images/graemlins/heart.gif[/img] 2[img]/images/graemlins/heart.gif[/img]
A good flop for me, obviously, as I had a gutshot straight/flush draw. If he raised without an ace, I could represent that while still drawing to a lot of outs if he called. As soon as the flop came down, he looked down at his cards, and I knew immediately that he hadn't flopped a flush (and something about his decisive facial reaction made me think he did not have any hearts).

However, he led out for half the pot (t6 into t12). I flatcalled, putting him on an ace or a queen trying to take the pot down then and there (or perhaps a simple cbet).

The turn came J[img]/images/graemlins/heart.gif[/img], giving me my flush, although almost the lowest possible flush. Villian again bet half the pot, and I called quickly (t12 to win t36). Normally I'd raise here, but stack sizes made this difficult(pot was about the same size as my stack), and I figured that a flatcall might 1)reveal more about his hand, and 2)scare him more than a raise. I didn't figure a raise on this turn would allow him to do anything but play perfectly, so I flatcalled.


The river came the 9[img]/images/graemlins/club.gif[/img], not likely to help him any. He thought for a few seconds, then checked to me.

In deciding what to do on the river, here was my thought process:
I have a flush, but I only beat one lower flush. If he has a hand like Ax6[img]/images/graemlins/heart.gif[/img], Ax7[img]/images/graemlins/heart.gif[/img], or Ax8[img]/images/graemlins/heart.gif[/img], he might be afraid of a higher flush and be hoping to check down the river. In such a case, I might be able to get him to fold these hands. Given my actions so far, which were very unusual for me (I'd been playing aggressively so far, and showing a mix of strong and weak hands) I felt that he was likely to read my passive line as strength, thereby making it easier for me to induce a fold.
I knew he would fold to any bet without the flush on this river.
Now I had to decide whether or not he had the flush himself.
Despite my initial physical read of him not having any hearts in his hand, he had led into a 3 heart board on the flop and again into 4 hearts on the turn. He had bet only half pot on the flop, and again on the turn, which certainly wasn't denying me the odds to draw. As far as I could tell, he'd paired an ace on the flop, and then possibly turned a flush, but whether it was a flush he would laydown was another question. If he didn't have the flush, I'd win at showdown anyways, and he'd fold the hand to my bet, so it didn't really matter.

After thinking about how he'd played the hand, and knowing our past interactions, I decided that there was simply no way he was checking the King or Queen of hearts on this river, as he would almost always lay in a final value bet in this situation. I figured therefore that he had an AxT-6, 4[img]/images/graemlins/heart.gif[/img], and I could possibly get a call from Ax4[img]/images/graemlins/heart.gif[/img] or a fold from the other hands. I therefore decided that the best option was to blockbet the river, betting 1/3 pot (t16 into t48). I had about t30 behind, and he had me covered by about 6-8.

What are your thoughts on both my line, and my thought process as it comes to reading his bets and hand?

Shortened HH for convenience:
Hero (~t72)
Villian(~t78)
dealt to Hero:
Jd5h
Hero calls t1, villian raises to t6, hero calls t4
Flop(t12):
Ah2h3h
Villian bets t6, Hero calls t6
Turn(t24):
Jh
Villian bets t12, Hero calls t12
River(t48):
9c
Villian checks, Hero bets t16