A Main universe in the Marvel Cinematic Universe created by Mark Fergus, Hawk Ostby, Art Marcum and Matt Holloway, it's also based on the Marvel Comics by Stan Lee.
What would happen if Marvel created a sitcom with all its characters? You can add actors that are already in the MCU or new actors for the role, as long as it makes sense. They should preferably be actors who could accept the role (even as a cameo) and who can do comedy.