I've actually done Fire-Earth before, to some extent...it was more like Fire with a handful of Earth cards as support, but still...
Seems like you could go quite a while without drawing a Crimson Dragon, and if the opponent kills it...although the Farenheit is always good supporting damage. Enchant Artifact works well with these, but maybe you should include a Fire Shield with all this, it would work well with the theme of your deck I think, delay until you kill them with Dragons...perhaps add a Plate Armor to defend these dragons a bit more...
Also, seems a bit heavy on the Rain of Fires, maybe take one of them off.
The one other thing is, although the idea of using Mark of Earth and no Earth Pillars is pretty cool, it has the weakness of mass dependence on Fire Pillars. If you can't draw any, or just draw one, you are in for a very slow game.