Scrying Pool really only works in digital games, or if vs. real people, in a non-real time game. The extra time to the game can add up.
Ditto with P-Stone
Just get rid of Possession. It's nice and all what it does, but it's not worth the rules headache and the weird way other things have to be worded for it to work.
I've read up (at least within the first 50 posts) the hassles of the tokens and such. Me, I would incorporate a once per turn policy (so no repossessing the same player multiple times in a row), and just make it that you ignore all tokens. Debt doesn't affect you when playing as the possessor, but then, you don't get to use any player tokens either (from Adventures, you don't get VP tokens, can't use coin tokens).
Herbalist is vanilla but I think it should be left as is. The Potion topdecking is useful within the set theme, and cheap +Buy is so scarce anyway. Maybe buff it to +$2 (yes, for $2).
Hmm, I would've suggested making the "top-decking" ability a "set aside" one so that you get to keep the Treasure AND the 5 cards you normally draw for Cleanup phase. However, effects that force you to discard down to x would muck with that. If you don't get the card back until the start of your turn, that does sound like a Duration. Not to mention straight up discarding x # of cards (like Torturer) would mess with this.
Golem and Uni are great as is. Vineyard is perfect, and I think costing P is essential to the card working so well and being balanced.
I thought University was too slow? Other than that, nothing else wrong with it
