Bureaucrat, Woodcutter, Gardens, Moneylender, Throne Room, Laboratory, Council Room, Village, Remodel, Market
Reasoning: Woodcutter and Gardens are possible, but Woodcutter is a weak enough enabler that it's not dominant in the same way Workshop would be. Bureaucrat is a soft counter to Gardens, or could be used in conjunction with the Gardens via the topdecked Silver.
Moneylender gives some early game trashing, which makes an engine possible. Council Room gives + Buy and enough card draw to make double-Province turns possible, if not extraordinarily likely, and the Village makes it possible to chain CRs. Throne Room + either Market or Lab could also provide village-like effects.
Remodel is another way to double-Province, and so provides some late-game decision-making opportunities.
This set is mostly defined by what is *not* present: Chapel is too good of trashing, Militia, Smithy, and Witch are game-warpingly dominant and strongly push towards a BM+X strategy, and Workshop would make Gardens the obvious choice.