I'd suggest dropping Jarad's Orders for Buried Alive . Sheoldred, Whispering One is better than Reya Dawnbringer . Finally I'd suggest maybe two more lands if you add other land ramp cards like Karametra, God of Harvests . Otherwise add about 4 lands since you already have some mana ramp, maybe more if you want to take more consistent advantage of your landfall.

At this point I am having a hard time cutting things for land.

I was looking at Sheoldred, Whispering One, but he is double the price of Reya Dawnbringer.

Have you checked the prerelease of sheoldred, don't know what Reya goes for but I know the promo is about 4 bucks on tcg.

I would suggest adding Bojuka Bog , maybe in place of a swamp or vivid land. I don't really think you need Prismatic Omen . In 5 color decks it's really good but you shouldn't be having mana issues in a 3 color deck. Skyshroud Claim is great at getting out your shock lands and if you want more ramp I would suggest Cultivate and Kodama's Reach . Sanguine Bond seems underwhelming here. Maybe another powerful creature here or Swords to Plowshares would better suit the deck. If you can get Sheoldred, Whispering One it is worth adding. Same goes for Elesh Norn, Grand Cenobite . Lord of Extinction is a bomb, especially in a reanimator deck. Avacyn, Angel of Hope is also great here as a reanimator target. Board wipes would help a lot and Dauntless Escort is great with those, as well as Avacyn. Decree of Pain is a great card for more draw and filling the graveyard. Kokusho, the Evening Star and Yosei, the Morning Star are fantastic reanimator targets as well. Krosan Grip hits Sensei's Divining Top and would help a lot. For versatility I would suggest Deathrite Shaman as he is a powerhouse. Bloodgift Demon is good for more draw and Debtors' Knell could a a fun card to consider. Karmic Guide is great and you can always make the combo with Eternal Witness and Reveillark . Fleshbag Marauder helps fill your grave and gets rid of some extra creatures and Disciple of Bolas gets you cards and life. Scavenging Ooze is great at keeping everyone else's creatures out of the yard and another good reanimator target is Acidic Slime for the versatility. I don't think you need Glaring Spotlight or Treasured Find and from what I've seen Vraska the Unseen is underwhelming in edh. Gavony Township is another utility land to consider. Geralf's Messenger seems a bit underwhelming as 2 life in edh is nothing. Loaming Shaman doesn't seem to do a whole lot either and Ghoultree is just a cheap 10/10. You already have Doomgape which has the same stats with abilities so I don't think you need Ghoultree . Keep up the fine tuning.

Thanks for the advice; some of the cards are a bit out of my price range. I know that seems odd given some of the cards that I am running. Geralf's Messenger I am trying to go do recursion so it just isn't two damage.

But to do that it requires multiple pieces, which would indeed be hard to pull off.

Emeria, The Sky Ruin + Prismatic Omen is what I am going for to reach the necessary amount of Plains .

I am not yet using the update feature because I have yet to actually finish the deck.

Perilous Forays and Skullclamp are bombs in my variant Kara-door To My Graveyard. Maybe check it out for potential other ideas. Realms Uncharted seems like a good card to cut as I don't really see it doing too much aside from getting your Strip Mine combo...

Also Recurring Nightmare (which is in your maybeboard) is banned in this format...

Coming back after 5 years. Updated and streamlined a little.