Islam; cut and paste religion with careful omissions and additions to manipulate the gullible, undereducated masses.
Can't speak to the various Jewish sects with much authority, I just know that I must protect their interests.
They also had the disadvantage of being developed after the full development of Christianity. They had to respond to it, while Christianity only had to respond to Judiasm (and did so appropriately). That doesn't excuse the omission (although admitted Jesus was the Son of God would sort of undermine all of their religion)...