I would probably suggest splashing white and running one or two Warleader's Helix instead of Mizzium Mortars . It's not very often you'll have the six mana to overload mortars when you need to (especially with only twenty lands), and that lifegain can really make a big difference late game, not to mention it works with Satyr Firedancer and Chandra's Phoenix and is at instant speed instead of sorcery (all very relevant).

I would also consider running maybe just one Fated Conflagration just as a more effective answer to a planeswalker, plus the fact that it can kill Palukranos in one shot is nice. And, on top of it all, it has the potential to provide more scry.

You should also probably sideboard a couple Anger of the Gods just because it's so good against RDW and can be good in a mirror match.