I'm not sure about the rest, but , if the Manhattan project can allow us to produce nukes, couldn't there be a prophet-constructable wonder which grants the construction of crusaders? I still think the crusade should be a national wonder and crusades usually were usually led by great kings not prophets. Jihads, however, would fit this description perfectly. They could be prophet constructable world wonders. Anyhow, I think I'll produce another list with some more potential religious units. I think I can come up with quite a few more if I get creative.