have you considered using Knight of the Reliquary? I think it would be a good fit, considering you are G/W and also running Crucible of Worlds.

While tempting, Knight of the Reliquary's activated ability requires me to search my library. If I have Leonin Arbiter in play, paying 2 for Knight's ability suddenly isn't nearly as appealing. I still might give it a playtesting run and see how it interacts overall.

Crucible of Worlds is really only there for the possibility of infinite Ghost Quarters, though I don't yet know if it will slow me down too much or not. I may have to replace it, but I'll get to that when it comes up.

fair enough, a little like the whole wasteland combo. I think it would be fun to be able to use it, honestly.