If I could make a change to just ONE scene...
At the end when Peter confronts Vulture at the warehouse, I would have KILLED for them to have an exchange like this:
Vulture: You could have stayed at the dance, Peter! You could have looked the other way!!
(Peter looks down)
Peter: I already 'looked the other way' once... And I never will again!
(Fight begins)
BOOM. That's how you mention the origin without showing it. Or, at least, that's how I'd do it. Thoughts?