I'd really like to have lots more stuff at the level of quality of the (embarrassingly, also Yvain's) Non-Libertarian FAQ arguing for progressive views, but don't really know where to look.

I will point out that the Non-Libertarian FAQ isn't actually anti-Libertarian; it's targeted at a specific (vocal) branch of libertarianism, which I'd call Moral Libertarianism. From the FAQ:

To the first type of libertarian, I apologize for writing a FAQ attacking a caricature of your philosophy, but unfortunately that caricature is alive and well and posting smug slogans on Facebook.