Some of the differences are more fundamental, since the split from the Orthodox-Catholic branch of the Christian faith was very early. But yes, to the Western sensibility, the Copts are “hyper-orthodox.”
The Ancient Egyptians embrached Jesus early on and after some desputes with their Gnostic Brothers they became the beacon for the new Christian Church spreading into Africa to the Sudan and Ethopia. Blacks were celebrating Jesus while much of Europe was still pagan. The Copts are perhaps the most pure to the ancient ways and beliefs. This may well be why apparitions of Mary and Christ are experienced by them. The cornerstone of Ancient Egyptian religion was the concept of eternal life, one that is key to the Christian Church as well.