All the talk about Misfits is focusing on the weirder rules implications, but I'm trying to figure out how often I'll even want it. I looked at a few random tables and sure, sometimes I could see some nice uses (Baron if you have an Estate, Monument if you don't; JoaT until you need it to be Tournament). But other times it would be like, Moat with no reaction/Great Hall with no VP, or Pawn/Smugglers/Masq/Brigand, and man, that is not flexibility I need.
Some ideas:
Village + Conspirator - Substitute any $2-$4 cantrip for Village. Basically, Misfits becomes a Conspirator if those are activated, and a Conspirator-activator if they aren't.
Hag/YW + All-Purpose Card - Issue curses until they run out, then be a Caravan, Oasis, Pawn, or whatever other general-purpose kicker card might be available.
Trasher + All-Purpose Card - Be a Chapel, Moneylender, Spice Merchant, etc, until you've trashed down enough, then be something else.
Collider + All-Purpose Card - Some cards only work if they collide with other cards. Be a Throne Room, Treasure Map, Baron, Crossroads, Tournament, Coppersmith, etc, only if the hand is right for it. Otherwise, be something else.