Rally the Ancestors doesn't work good without a sacrifice trigger. You loose the allies at your next upkeep and they don't get haste. It will trigger
Rally on your Allies, but won't enable you to attack. I would replace those with
March from the tomb or add
Ayli, Eternal Pilgrim so you have a sac outlet. I would also replace
Brutal Hordechief with Drana, Liberator of Malikar. She's an Ally with a good upside, she doesn't drain herself, but can help your creatures survive combat and do huge damage.
Eldrazi Displacer would also allow you to
flicker an Ally to trigger the life gain/drain with
Kalastria Healer, but it does require several colorless sources. You have
Caves of Koilos that provide colorless, but I would think you would want about 3 more sources to be sure you can trigger it.
I'm not sure I would run
Ondu Rising, I think you would be better with
Lantern Scout. If you are going to mainboard a discard spell, I would choose
Duress over
Despise. If you are concerned about creatures, I would run more creature removal. The other option would be something like
Painful Truths so you could draw cards. One of the challenges decks like this have is running out of gas.
Painful Truths helps you avoid that problem.