Thoughts:
Game 1: I don't know whether Remodel/Grand Market is actually much good in Province games, but anyway there's no good BM option, so I go for it, and so does yuma. A combination of Cellars, Villages, and Watchtowers later on allows for a surprisingly good engine, and I'm able to end it on piles. I'd love to see what a strong engine player would do with this kingdom.
Game 2: Tactician/Black Market... and Coppersmith. (Crossroads helps a lot too here.) To give an idea of how crazy Coppersmith was here: on my second-last turn, I have $31 to spend on a turn where I play a Tactician. I thought I was dead when yuma got Goons out of the Black Market, but the game wasn't long enough for the VP tokens to dominate. The Haggler I pulled helped a lot.
Game 3: Ghost Ship and Duke seem key here. I move to Duchies sooner than yuma, winning the split 5-3, but then he gets a 6-2 split on the Dukes. He tries to run out the Estate pile before I can pull ahead, but a good turn 23 (aided by his Ghost Ship play the previous turn) gets me a Province, and I'm able to tie it. In hindsight, maybe it's worth skipping Ghost Ship entirely: a single Ghost Ship play almost seems to help when aiming for $5.
(At this point, I'm guaranteed at minimum a tie in the series.)
Game 4: I think Tactician/Mountebank will wreck any sort of engine, but yuma puts together something reasonable with Highway/Crossroads/Tactician/Haggler (and Mountebank too, of course). I resign once it becomes mathematically impossible to win.
Game 5: A Festival/Envoy engine enabled by Chapel. We both make the dumb move of getting a Pirate Ship, and neither of us get more than a single token on it. My thought was that, since he opened Envoy/Chapel, I might be able to prevent him from hitting $5 for a Festival, but it failed. Anyway, maybe because I'm first player, I manage to get a 6-4 split on the Festivals. My engine is consequently stronger, so I'm able to win.
Few more misc. thoughts on game 5: an engine is clearly the right play here, because BM+Envoy will get wrecked by a Pirate Ship engine. I make a dumb play on turn 14 when I trash my Silver because I'm scared of Pirate Ship; even if he hits it, his Ship would only be a terminal Silver. When playing an Envoy engine, I like to play as few cards as possible before each Envoy, so that my opponent doesn't know how many actions I'll have when picking a card to discard. yuma didn't do this hiding technique, but it didn't matter much.