Hahaha! I wouldn't give up any of them, with the possible exception of Scout. Maybe Rebuild.
Here is a love letter to the cards others hate:
1. Chancellor: Better than silver if the only terminal, teaches you the value of a good reshuffle. I've played a fun Chancellor-BM game before. Obsolete if the more interesting Scavenger is on the board, but that doesn't happen too often.
2. Tournament: Overpowered? Perhaps. Still, I've always had a weakness for its lovely $4 Peddler effect. It helps you build up your deck in an excellent way.
3. Coppersmith: It might go 20 games without working, but the 21st will be a joy. Especially with King's Court. And speaking of which...
4. King's Court: Overpowered? Certainly. But much like Chapel, and unlike Rebuild, it's overpowered in a synergistic way. It makes your other cards more interesting, not less. Pawn matters more when KC is on the board. So does Coppersmith. The only cards that would be left out of an engine due to KC's presence are the villages, but even then the Festivals and Worker's Villages and Plazas still benefit tremendously from it.
5. Goons: Just as synergistic as KC, maybe more. It's nice as a BM card, if you play 1 a turn. It's only obnoxiously powerful in an engine... but it works best in engines that are strong to begin with! It's a non-drawing terminal, which makes the villages more important. It's a discard attack, which makes draw more important. Heck, the mid-game copper purchases make trashing continue to serve a purpose in your deck up until the very end! Once again, it's OP, but highly synergistic.
6. Possession: It's... actually kinda awful if you lose to this, especially with a megaturn deck.
Okay, so maybe Possession really does suck. Still, I'd keep most of Dominion's cards. I'd gladly keep them!