Green Arrow/Hawkeye/Black Widow are Hunters
Dr Strange/Red Skull are Warlocks
Definitely Dr Strange, red skull not so much.
Titans - Colossus / Thor / Iron Man
Warlocks - Raven / Loki / Dr Strange
Hunter - Batman / Green Arrow
Can't believe you guys are forgetting MCU Scarlet Witch for female Warlock.
Just MCU characters:
Titans:
Hulk
Cap
Iron Man
Thor
War Machine
Drax
Winter Soldier
Thanos (don't even need to wait for Infinity War to classify him. He's strong as hell without the Infinity Gauntlet.)
Iron Monger
Hunters:
Black Widow
Hawkeye
Star Lord
Gamora
Warlocks:
Scarlet Witch
Loki
Doctor Strange
Aldrich Killian (wasn't sure where to place him but I remember he ended up regenerating his limb. Yeah, it was due to Extremis but guy can be a sort of a Sunsinger because of that. Yeah, I'm reaching here.)
Undecided:
Vision - he's a powerhouse so he could be a Titan but he has this mystical presence about him that could make him a Warlock.
Quicksilver - not sure about this one at all. Leaning towards titans just because they're the fastest of the classes.
Groot - leaning towards Titan but undecided.
Rocket - so leaning towards placing him under Hunters
Falcon - yeah, kinda stuck on this one
Ant-Man - same as Falcon
Ronan - same as above
Black Panther - need to see Civil War first before making any judgement but leaning towards Titan
Spider-Man - like Black Panther, I need to see Civil War first
Red Skull - want to classify him as a hunter just for how crafty he is
Ultron - they did him dirty in the movie. Don't even want to place him under any class. Yeah, didn't like the MCU Ultron.
The main baddie from Thor 2 - yeah, I don't know his name. That's how much I care about that movie.