I might just be blind, but I don't see a
Storm-Kiln Artist in there. I definitely recommend it: Making one extra treasure back for each shot of the "gatling gun" will accellerate you insanely fast, as well as let you chain together 2-cmc spells instead of just 1. On top of that, te
Storm-Kiln Artist can get insanely high-powered with enough Treasure. Definitely worth the slot imo.