That is the issue. I like the Pines as villains, but no matter how I shift it I can't see Gideon as a good kid.
My first read about the Rev!Pines universe was this-
Which kinda makes sense to me, in the sense of the two being halves of a whole, even more so considering how...
close these two are sometimes shown to be. They have each others reigns, but the purity of their essence makes them all the more dangerous, especially if the other is threatened. Really, the only suitable opposition I can think of for the Pines is...really, the Pines, some horrible accident with the portal or some mess brought about by Bill, it would be strange to see.
That said, I'd also heard
another interesting idea that the Rev!Pines are still actually good people, good-hearted performers and mages who like to show off, but have to constantly clean up the messes left behind when Gideon gets in over his head trying to impress Mabel, while the superstitious small town folk think nothing but the worst of them.