The best deck I ever ran was King's Court + Grand Market + Goons + Watchtower.
Extra actions from KC+GM followed by 2 Goons, Watchtower to draw cards, more KC+GM. Buy Colonies and spend the remaining buys on Copper, trashing the Copper with Watchtower. I was amassing 26 points in VP tokens and however many Colonies I was able to buy each turn. I emptied the Copper pile in about 4 turns.
--
"Coinflip is sacred."