Can I ask, why not use non-upped Phoenix instead of the crimson dragon? You can play them off the first immolation, and they are effectively 2-3 more RoL in the deck, allowing you to sacrifice something in case your opener has no RoL, but has cremations, lava destroyers, and dragons (which would be phoenixes, in this case).
And they let you do dumb things like an opener of 2x Phoenix, 1x Lava Golem, 2x Cremation. That's 30 damage on the second turn. Let alone the nuts opener of 2x phoenix, 2x lava golem, 3x cremation, which is an astounding 46 damage, second turn.