Vulture
Who should play him? Colm Feore is rumoured since he's portraying Adrian Toomes, and I don't see why he wouldn't be a good choice- he already looks like a more physically able Richard Jenkins! John Malkovich was supposedly locked in to play Adrian Toomes when Raimi wanted Vulture as the villain for his Spiderman 4, but in all their wisdom Sony shut that down. I don't see Malkovich working under Marc Webb's direction, but this was a missed opportunity- imagine if he gave a performance like Willem Dafoe's Green Goblin! Colm Feore does sound like a solid choice, to be fair, so let's stick with him.
Why would/should they be included? I'd love to see how you do a villain like The Vulturein a way that is both cinematically viable and genuinely villainous. Because the whole concept of him seems ridiculous! A bald dude who can fly in a fur-trimmed green suit- hmm... I'm sure there's more to the character if I read popular arcs with Adrian Toomes in them, but I think my opinion is echoing what most of the public will be thinking as well. And since he was part of the original lineup like Electro, he should be included because he's one of the few in the lineup who hasn't already been covered in Raimi's trilogy. So the Vulture seems to be both a massive challenge and a great opportunity. But so, potentially, was Electro and Bane, but their reinventions have impressed most thus far.
Likelihood: 4 out of 5 Since he came close to appearing on our screens less than a decade ago, he's clearly a villain that's been in mind for a while now. Adrian Toomes has already been cast, so unless they really want affairs to get crowded, I'd say he's another safe bet like Electro, especially since he'll likely be linked to Lizard, and possibly Electro if he becomes a new prisoner at Ravencroft by the end. But then, we don't know the character's fate, and it may be that he stays Adrian Toomes and the Vulture never comes to fruition. By this stage, however, that seems very unlikely.