Spidey could definitely be black. He was an orphan who grew up in a bad area in New York city and then his uncle got gunned down. Then he got bit by a spider and figured he'd start patrolling the streets. And he has a mask on, so everybody probably thinks he's white anyways. And if you need a nerdy black scientist to play him, Jaleel White probably doesn't have shit to do:
Or, wait, actually, I just realized, they already did a movie with the plot of Spiderman using a black guy:
The bigger question is, what color would Mary Jane be? If you're gonna keep her white, then you gotta deal with some interracial dating questions or else it'll be the elephant in the room. If you're gonna make her black, you still gotta keep her hair red, because that
is central to the story:
Either way, Michael Keaton is the one true Batman.