*cracks knuckles*

Cloud never died to save anyone. You could say that he almost died when (SPOILER) he got sucked into the lifestream but that was only because he was bugging out about his true identity. Also yeah, Cloud didn't impregnate Tifa that we know of. Tifa starts trying to admit that she has feelings for Cloud at one point but nothing definite happens. Also, Sephiroth didn't get crucified, sorry. Him raising his arms doesn't allude to that any more than Cid holding his spear back so he can strike with it is an allusion to Zeus. Also, Tifa is far from a Mary type. Mary was born without original sin (or whatever, damn Augustine), whereas Tifa was kind of a mean brat to Cloud when they were younger. That's another huge flaw there, Tifa and Cloud grew up together. Yet another one is that clearly, humanity was not wiped out because they're releasing a sequel in the form of a movie that stars Cloud and Barret among others.

If anything, Aeris is the Jesus figure.