The religious aspect though must be carefully taught. Time studying Christianity should be equivalent to time spent studying Judaism or Buddhism, or whatever. It should be taught from an anthropologist’s point of view.
This I disagree with. I think more time should be spent on Christianity for two reasons:
1. It's the world's largest religion. 2. It's more culturally relevant. For the same reason that pupils from any given country spend a disproportionate amount of time studying the history of their country; the prevalent religion both currently and historically in that country deserves extra attention.
I agree with your second point though, religious study should look at the practices, beliefs and history of a religion. I see no reason to spend much time at all on studying the Bible in religious study classes.