Odd that TappedOut gives me 100% competitive with Pyretic Ritual but only 97% with Desperate Ritual even though it's a strictly better card.

Would you mind including your sideboard? Its important to get a picture of the full 75 cards, especially with budget decks.

Knowing that you have a sideboard plan which is 15 land destruction spells, or 15 artifacts to side all of them in as madcap hits helps a lot with planning. Red doesn't have great enchantment removal, and tends to rely on janky artifacts or splash colours to fix that- its why its boros or naya burn, with even 'mono red' usually splashing for Destructive Revelry.

You might end up reliant on Blast Zone to kill Phyrexian Unlife which will make ad nausiem/solemnity matchups unpleasant.

In terms of keeping pyrohemia in play, some cheap manlands will do a lot - Lavaclaw Reaches or Ghitu Encampment might not be fantastic manlands, but they will work fine for that.

Thanks for the suggestions!

At the moment I don't play a sideboard on this deck since it's more "for fun" deck. However, if I did I'd probably go with switching:

4x Zhalfirin Void for Blast Zone

4x Slagstorm for Ratchet Bomb

4x Simian Spirit Guide for Goblin Cratermaker

3x Magma Jet for Abrade

Also, good idea with Ghitu Encampment although I'd probably go with Blinkmoth Nexus, Inkmoth Nexus, or Mutavault since they tie up less mana.