Help with Be'lakor

As Title say, im trying to build my fiance a bracket 3-4 Belakor deck, just Demon Tribal, nothing broken, but at least able to keep up with other decks like Kaalia. This is what I have, but wondering what to do to make it stronger? https://moxfield.com/decks/Orip77mCtkS_2o7qtcJc9Q