For people who think Black Market is one of the best: how do you do the setup IRL? It sounds unusable.
The promo I most recommend is Governor. It's a very centralizing card, and difficult to figure out too. If you like centralizing cards, then second and third place would be Black Market, and Sauna/Avanto. If you prefer cards of more middling strength, try Prince, Summon, Dismantle, and Envoy. Stash is widely regarded as very weak, and Walled Village is basically never better than village.