I personally would like Spider-Man 4 to deal with the Lizard and Kraven. A cameo of Dr. Adrian Toomes who mentions creating his suit (maybe on TV or something). Sandman, for one scene at the near beginning of the film mentions he is leaving New York with his family trying to escape his criminal record. Then an after credits scene with Maxwell Dillon becoming Electro. Spidey cures Lizard at the end of 4 and Kraven has gone missing. In Spider-Man 5 he fights Electro and then later Adrian Toomes who has recently become Vulture. A short cameo by Quentin Beck (maybe one of MJ's Broadway show's has a sign with his name on it as the special effects creator). Electro is eventually captured by the cops and is placed in a high security prison. Vulture escapes then later finds Doc Ock washed up on the shore and takes him back to his lab... Maybe during one of Spidey's fights we see Iron Man on the top of the Empire State Building watching Spidey (small cameo). Then for Spider-Man 6 Vulture revives Ock and the two of them decide to start a criminal team. Quentin Beck becomes Mysterio. Ock and Vulture break Electro out of prison and Sandman comes back to town after his daughter has died (after being refused treatment by a doctor). The 6 join forces against Spidey who defeats them after one huge battle. Ock, Electro and Vulture are placed in prison. Mysterio escapes from the cops and Sandman comes to Spidey to ask forgiveness again. Spidey refuses to forgive him; Sandman leaves. Kraven continues to hunt Spidey. Final Battle: Kraven's Last Hunt. Kraven shoots himself after drugging Spider-Man and burying him alive. The final shot is of the beaten up Spidey breaking free of his grave then swinging in the rainy night. After credits scene: Iron Man meets Spidey in his apartment and tells him about the Avengers (all taking place after "The Avengers" film.)
Avengers 2:
Iron Man introduces Spider-Man to the Avenger team. Spidey is shocked to see Sandman as part of the team! Eventually Captain America, Hulk, Iron Man, Ant-Man, Wasp, Sandman and Spider-Man all fight as The Avengers... plot subject to change...
That's my idea. And in between Avengers 1 and 2 there can be several Hulk, Iron Man, Cap. America, Thor, Ant-Man and Wasp films to fill in the gaps between the two films while they're waiting for the Spidey series to conclude.
That's how I'd do it. Then possibly in the future of the Avengers some supers can leave and some can come back. Maybe even see Wolverine as a cameo... Bring in villains from every film. Doc Ock, Magneto, Mysterio, Carnage, Hobgoblin, Bullseye, Leader, Mandarin, Dr. Doom, Silver Surfer, etc...
