High risk, low reward, overly elaborate prank that gets her bodied by birds. Classic tragedy premise.
Melanie is a prankster bird deity akin to Loki and the birds cause mayhem to try to awaken the dormant goddess inside her.
No Deus here. Just humans. Even Ava.
Let's say Ava was a captive human instead imprisoned by her father, would you blame her for being so manipulative?
Nathan manipulates Caleb. Ava manipulates Caleb. Caleb manipulates Nathan.
I think the film isn't to scare you about the inevitably of Turing-Test-passing-AI, it's to scare you that they're just a reflection of us.