Trasher village
$4 - Action
+1 card
+2 action
Trash a card from your hand
The problem with this one is that when you want villages, you almost always want a lot of them (except Walled Village). But you can't afford to have a lot of Trasher Villages because pretty soon you'll thin all the crap out of your deck and be unable to play them. So chances are that if you buy Trasher Village, you're doing it for the the non-terminal trashing, not for the +2 Actions. That means it's basically "+1 Card/+1 Action/Trash a card from your hand". That might be an OK card, but there are cards that do non-terminal trashing better or in more interesting ways (Lookout, Junk Dealer, Forager, Upgrade, etc.). So I don't see Trasher Village adding much to the game.
Cantrip remodel (or grand upgrade)
$7 - Action
+1 card
+1 action
Trash a card from your hand. gain a card costing exactly $2 more than it.
I guess this might be OK, but I think it'll play very differently from Upgrade. Hard to say how it would work out without playtesting it.
Victory village
$4 - Action
+1 card
+2 actions
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Worth 1 VP
Doesn't add anything to the game that Great Hall doesn't already add. In general I'm against tacking VP onto a card without the VP being integral to the card concept in some way. For Great Hall, the added VP is itself the concept. It's a Victory card that doesn't "take up space" in your deck, and it has cute combos with some other Intrigue cards (Ironwoks, Tribute, Scout, Conspirator, etc.). Likewise, Harem's concept
is VP/Treasure. It fills that slot. As far as I'm concerned, we don't ever need another Treasure-Victory card. Nobles gets a bit of a pass, being from Intrigue.
Anyhow, Victory Village is pretty much the same card concept as Great Hall, so I don't see the need for it.
Duke of estates
(something which give a number of points per estate in your deck at the end of the game).
I worry that there's no way to make this good enough to be worth going for, yet not so good that every game with it becomes a rush for it. Also, Duke pretty much covers this concept.