1)If we are talking about river I believe nope. Most people can't construct x/R range; bet turn and balanced x/R river bluff/value range. Which gives us bit more EV as a bet.
2) Yes, our hand is good bluffcatcher. For your size I guess you can bet 4x+ if you have those. After all I think your sizing not correlate with your range, you aren't have weak hands to bet this size. You valubetting flushes+ here and most of your floats have Ah which is pair now.
So sizing up
3)...... Sorry can you say again
4) Doesn't matter if no reads

5)I'd play as you till river. But in river I would bet 2/3 with this and my bluffs are QJ/J9 one heart and Khx. And would be calling topX of my range according to his size (~ 35% of the range). Kinda hard to tell which flushes are better bluffcathers but one high and one low is great one (Q2 for example, K2 too because not blocking medium bluffs).
His bluffing range hard to tell, but I imagine nl200regs will find enough, however their value slimmmmmm (T4/84 not flop raise at high %, 88/TT 3betting pre)

I think Villain has Ahx bluffs a lot more here than the goods. Once he sees he is not going to win showdown vs Tx he decides to check jam repping AhAx or A high flushes since he's blocking the only boat you can have(A4). I think I might prefer a river check back tbh...