I was just thinking about all the super hero movies ive seen over the years (from Batman 1966 to TWS) and realized the main reason I enjoy the MCU movies the most isnt because of the SFX or the action sequences, its because I simply love the characters and their relationships in that universe. Like if The Avengers wasnt written by Joss, I probably wouldnt care for it as much. It would just be another action movie to me. The way he brought his unique sense of humor and love of the characters to it, made a huge difference. It takes it to another level. You enjoy just hanging out with these people even when theyre sitting in a room. That is something important you cant duplicate. Its his personality and respect for the material that makes it all work so well. Other super hero movies might be entertaining, but if you dont have a filmmaker that is putting their personal stamp on them and just treat the productions as a "job", they wont come across as well as they could. Of course most Marvel characters are already great, so that only helps when adapting them to film.