Haven't gotten too much chance to try them, but other potential adventures combos/synergies that might be decent:
1. Highway + Seaway: This one's pretty straightforward, get a highway, seaway the highways, then get as many highways as possible. 8 highways and you can buy all the provinces. With good trashing, this might not need much else.
2. Wine Merchant + Distant Lands: This one admittedly might be dubious at best, but the idea of having a deck drawing engine with a few extra actions, and then alternate turns between playing wine merchants to buy distant lands, and playing distant lands, returning the wine merchants to your deck to repeat seems nice to me.
3. Alms + Duplicate + Gardens/Silk Road: A new version of a gardens rush, if you get duplicate on your first two turns, you're netting about 2 cards per turn on average for the rest of the game, and you don't need to buy treasures to keep your economy going. You can also manage when you call your duplicates to control what you put in your reshuffles if it helps at all.
To me the first one seems actually quite good, not sure so much about the other two. They're mostly just the result of me trying to find uses for Wine Merchant and Duplicate.