Which villain should be in Amazing Spider-man 2?

With Amazing Spider-man swinging his way to the theaters (thwip, thwip), we are now asking ourselves: who will be the next villain for Spidey to face?
Spider-man has a whole load of villains which haven't been used in previous films and I would think that some of them would do rather well in a Spider-man movie regarding to the story of what we have gathered from different videos and trailers.

I believe that maybe the original Vulture (Adrian Toomes) would make a good villain as he is a scientist and might have something to do with Peter Parker's back story as his father was a scientist and may give a reason for his parents disappearance. I chose this villain as he is not well known movie wise and I think that him being the villain would allow battles high above.
Another villain that would make a great rival would be the Green Goblin as he would be able to face Spidey physically and mentally.
Which villain do you think should be in Amazing Spider-man?
Please feel free to comment!