Yet, as you yourself have stated many times, the ideas of the Judeo-Christian faith themselves stem from more ancient African sources.
I wouldn't say so much that Rastafari is 'rooted in the Judeo-Christian faith', as that the environment of the first modern-day Rastas was (and still is) steeped in this faith, hence in attmepting to reconstruct an African identity there was little else to draw on. I dare say that had the dominant faith in the area been, say, Hinduism, people could still have looked into and re-interpreted it and come out with the same basic philosophy as Rastafari, including Haile Selassie as divine (an avatar). Indeed there was a strong Hindu influence on Gungunguru Maharaj's (Leonard Howell's) ideas.
Put it this way, the Rastaman (or woman, but more likely a man in those old days) would go up in the hills, in nature, and get wisdom directly from the source (Jah/Mama NTR). Then he would go back to the city, pick up a newspaper and a Bible, and 'translate' this inspiration to specific terms that people could grasp, in their idiom. Their idiom being the Bible (the only book most people had ever read, those few who could read that is) and current events, especially events in the Motherland. So rather than being 'rooted' in Judeo-Christianity, I would say Rastafari used the tool of Judeo-Christianity to communicate with the masses, as this was the only tool available.
Walter Rodney used the tool of Marxism-Leninism (which in my opinion is full of both truth and flaws, much like Judeo-Christianity) to communicate with people. But essentially he was a Rastaman, in that he had the same goals and same basic philosophy, just not in a Judeo-Christian format. That's why there was so much mutual respect between him and the Rastas.
In Guyana and the Guyanese diaspora, the Rastafari are really the free-thinkers of the society. Rastafari is what tends to attract those people (African people at any rate) who think critically, question the status quo and the world around them, and there are many varieties of Rastaman and Rastawoman beyond the fundamentalist Bible-basher. There are those who see Selassie as JAH, as Christ, as a role model and nothing more, as a powerful ancestor, and other interpretations. There are also a few Indian Rastas who come from a Hindu or Muslim background, rather than Judeo-Christianity. I think the common denominator among G.T. Rastas who I've met is we like to reason, to debate, and aren't afraid of stirring new ideas into the mix. The first time I heard Rastas expressing ideas like being strongly against patriarchy, against even homophobia, acknowledging Kemet as the source of much of the Bible, and so on, was not on this board from the moderators, it was from my G.T. idrens and family. And many of THEIR idrens and family in the Rasta community have more sexist, or homophobic, or Bible fundamentalist ideas, this doesn't stop them from getting along fine, differences of opinion don't mean we have to separate ourselves into antagonistic groups.
Then again there are quite a few 'Rastas' in G.T. who are involved in gangsterism, drug-dealing, etc., all while professing the Rasta philosophy, or using such to justify their activities. I don't know if I can even really condemn them, though, until I've been in their shoes, cos Jah knows it's hard back home (which is why so many of us live elsewhere) and when your youths are hungry you're gonna make sure your youths eat by any means.
Well I guess the point of all that rambling is that Rastafari is more than a 'Judeo-Christian' movement, essentially it's a poor people's survival movement, meaning not only physical survival, but spiritual and mental survival. As for Haile Selassie, consider one aspect: the psychological effect for desperately poor people who have been given inferiority complexes to identify with a fabulously wealthy supreme African monarch, perceived as embodying all the qualities of justice, fairness, intelligence, strength and courage that people seek to cultivate. Consider the psychological effect of seeing a photograph of someone you see as JAH firing a machine gun against a fascist army. For people who have been brainwashed for generations by a distorted version of 'Judeo-Christianity' that tells them it is their lot in life to be poor and meek forever, the effect is powerful and liberating.