With Spider-man's imminent arrival to the MCU, everyone is concentrating their thoughts on how the web-slinger will fit with the Avengers.
But what I think is more important... which foes are fit for the MCU. This is a list and why are they perfect for the next phases.
Adrian Toomes could fit in various ways.
He could be the creator/designer of the EXO-7 wings Codename "FALCON" that appeared on Captain America: The Winter soldier, maybe that could be developed by HAMMER or STARK industries or a "new company" (Oscorp). But since is in the MCU, a "Howard Stark betrayal to his apprentice (Toomes) angle" could be very good so we have three heroes for him to have a grudge. Maybe his wings could be an upgraded version: The EXO-10 VULTURE.
His Origin is tied with some MCU characters like the Hulk, The Leader and Abomination. He kidnaped Colonel John Jameson (J.J. Jameson's son) on his origin story in the comics, which is a perfect blend for what I call: the Marvel's "Military Universe" that includes Flash Thompson (Agent Venom), Silver Sable, General Thaddeus E."Thunderbolt "Ross (Red Hulk), Carol Danvers (Captain Marvel), Colonel James Rhodes (War Machine), Frank Castle (The Punisher), S.H.I.E.L.D/Hydra and lots more. He could be a formidable villain in the MCU.
Now with Marvel's "Cosmic Universe" started in Thor and Guardians of the Galaxy it's only logical to bring this "alien" to the MCU.
Marvel have to introduce us to Eddie Brock as a character, a movie or two before Venom appears. Not like Sony did. He is one of the most important Spiderman foes, so it have to be with patience and with "cosmic" intervention. With Infinity War's blend of "Universes" and storylines it would be really easy to plant the symbiote on Parker or at least on Earth. Then with Venom on the scene...Carnage is just a question of time.
Morbius and Kraven "The Hunter" among others can blend perfectly in the MCU or the MSU "Marvel Shows Universe' (Netflix , ABC, etc.)
Which Spiderman foe is best suited to fit the MCU right now?
Watch Spiderman in MCU action in anticipation to Avengers The Age of Ultron.