Solving the Puzzle

Supply

Synergy

Medium (56)
Engine 80%Trash-for-benefit 65%Duration 33%
Conspirator + cheap cantrips Conspirator + Artist

Cheap cantrips are easy to chain three Actions deep, turning on Conspirator's +Card +Coin bonus.

Variety payoff + broad gainer/+Buy Artist + Ironworks

Fairgrounds/Museum/Horn of Plenty want many differently-named cards; Workshops and +Buy make one-of shopping cheap.