I have done about as much studying as I can short of apprenticing to a house ...
And it seems to me that Ifa is really the African backbone of the "New World" diaspora currents, like Vodou, Umbanda, Quimbanda, and Santeria.
I would love to have a discussion of how the Ifa Orisha's were synchretized into the lwa of vodou. It seems to me that there are direct correspondences, such as Esu=Legba.
But I'm certainly no expert, and so I toss it out to the members. I know we have a few houngans, mambos and babalawos floating around.
Specifically with Haitian vodou, there seems to be a deep core of what is essentially Ifa spirits, that then is added free masonry, Catholic saints, etc. to produce Vodou. I don't mean to overly simplify.
But I think it's very interesting to trace back the true African sources.