Right so the basic concept here is sort of two seperate paths you can go.
Consume Spirit still requires black manage to pull off so I dont like it in the deck flat out.
Right now you're focusing alot on stuff like Cabal Coffers and Urborg to give you Black Mana so you can exsanguinate/gaze. But at the same time you're focusing alot on All your elves to boost out Mana and they dont really tie into each other all that well.
I guess I would say I see three Potential decks here that do similar things but in slightly different ways and you've tried to put 2-3 of them all into one deck!
Deck 1 - Black Consume Spirit/Exsanguinate/Lifedrain Deck
Cabal Coffers, Urborg, and creatures like Nirkana Revenant and (I cant remember the other one now...) who let you tap for extra Black Mana are key here.
Deck 2 - Green Elf Mana Ramp into Assorted Expensive Cards.
Nykthos, Archdruid and Priest of Titania provide you with huge gobs of Mana. Which you then use to play World Spine wurm or something else big like that.
Deck 3 - 12 Post Variant
The 2 Locus + Thespan Stage + Vesvuva and then a few odds and ends like Voyaging Satyr to untap your Locus again. Use your huge wads of Colour Mana to Fireball or Emrakul someone to death. Fun!
I just think you're trying to do too much at once in your current deck.
Candelabra of Tawnos was the card I was thinking of. It let you abuse the heck out of lands like the locus.
Also Note: Gaze of Granite is just a worse Pernicious Deed so if you're gonna be playing competitive legacy look for the deed!
Modern Decks can consistent get off a Turn 4-5 Emrakul Im 100% Sure that Legacy can do the same or better if needed.
If you're looking to play more casually my advice still stands. But you can get away with playing a deck much closer to what you showed us without any problem.
Paradise mantle just really has very little to no use in the deck.... You'd be better off with Expedition Map or Sylvan Scrying so at least you can grab a useful special land. Actually now that Im looking at it again Elves of Deep Shadow or Lanowar elves would probably be better than Heritage Druid as well. Again all your stuff except heritage taps for mana already...so do we really need the one to enable non tappers to do it?