In a Moviebob-esque tangent, how would you introduce Miles Morales in the MCU, and what would be the villain that would bring him and Peter together? Miles Warren?

Good question!

I would have Miles show up as a supporting character in the next couple of Parker Spiderman movies – introduce him through Aaron Davis (b/c Donald Glover is awesome), maybe he visits Midtown Science as part of a middle school trip, have him hang out with Ned et al. 

That’s the important part, more so than the villain: making him a known, sympathetic figure who the audience will accept taking up the mantle.