The game is fixed limit A-5 triple draw HU, we're both plenty deep and pretty new to A-5 but assume generally competent in game basics with no particular reads on one another.

Hand 1
Predraw: I raise button with 98742, big blind 3 bets.
1st draw: 1/_
How many should I draw? How many should I draw had bb drawn 2? How many should I draw had bb just called and drawn 2 or 3?

Hand 2
Predraw: button limps, I check with KJ854.
1st draw: 2/3
Flop: I bet with 84555, he calls
2nd draw: 0/2
Turn: I bet, he raises, I 3bet, he calls
3rd draw: 0/0
River: I bet...
3bet bluffing as a snow is not going to be a regular play but I just felt like putting my foot down here since I hadn't snowed in awhile. Is it just suicidal to bet the river after I fail to get my opponent to break? What do we think the worst hand our opponent should call with on river?

Hand 3
Predraw: I raise button with T8752, bb calls
1st draw: 3/2
Flop: bb checks, I bet K7543, bb calls
2nd draw: 2/1
Turn: bb checks, I check back with 75433
3rd draw: 1/1
River: bb checks, I bet 76543, bb raises, me?
Was it too thin for me to bet river? What should my calling range be like? Should I have tossed the 7 on the 1st draw?

I'd draw 3 in all of these hands.

Would bet turn in hand 3, and river bet definitely not too thin.

Hand 1: I draw 2 regardless of how many my opponent has drawn. Admittedly this may not be correct, but if it's wrong it can't be by much. A 7 in A-5 seems like it is slightly worse than an 8 in Deuce but it's way better than a 9. I think we realize equity more drawing fewer cards.

Hand 2: Aggression is fine and you choose some decent blockers for the play. There is less breaking in A-5 but people may break hands like 7632A. But imo once he pats after you it is time to hang it up. It is a totally different dynamic if you are in position. There he may just be calling to see if you are making a play and are truly pat. Thus the opponent will fold more often when he is OOP. In that scenario I always launch a desperation final bluff and think it works often enough.

Hand 3: Totally standard river bet in a 1/1. This is a crying call. You can make an exploitative fold though if you know your opponent well enough but folding this strong would also leave you open to be exploited. I probably keep the 7 originally though that seems borderline. FWIW I snow the turn here with a rougher draw and having seen an extra 3 and 7.

Oh I missed the turn check in hand 3 in 2/1.

That's an automatic bet that you absolutely cannot miss.

I'm surprised to learn that was a bet on the turn. Glad to learn that now for pretty cheap than in Vegas this summer. The reason I didn't bet is because I had been cautioned to not overvalue weak 7s in A-5 after coming from a 2-7 background but maybe I compensated too far the other way. Is this a bet just because it's HU or would you make this bet in any HU pot in position even if the game were multi-handed? I know it's hard to generalize but please try

In Hand 2, villain called river with 7653A. I was surprised to see that hand pat vs the 3bet/pat since it's one of the worst 7s. Thoughts on villain's play?

The result of Hand 3 is I folded and got shown J532A. That was a bad raise bluff by my opponent, right? He should be doing it with pairs and not a hand as relatively strong (maybe even call worthy?) as a J5.

It’s automatic bet because you are a card ahead with one left and have a great deal of fold equity. It’s also a bet multiway if at least one player is still drawing 2. If called I snow because like you said it’s a marginal draw and pairing 3 also a blocker.

Regarding the 7653A hand the guy was probably calling because he beats a snow.

H3 I wonder if the guy was actually thinking he’d c/r that to knock you off a thin value hand as well as let you bluff your worst. My guess is he was steamed at missing his good draw and made a great play by accident.

Just to add about a multiway turn 2/1/1 spot, you should only bet the unimproved 1 card draw if you are last to act. If you check the last guy needs to bet