Jack's Marvel Cinematic Universe

Phase 1
Heroes:
 * Iron Man
 * Ant-Man
 * The Incredible Hulk
 * Captain America
 * Thor
 * Iron Man 2
 * The Avengers
 * Iron Man
 * Black Widow (introduced in Iron Man 2)
 * Ant-Man
 * Wasp (introduced in Ant-Man)
 * Hulk
 * Captain America
 * Thor
 * Hawkeye (introduced in Thor)

Phase 2
New Heroes: 
 * Captain America 2
 * Thor 2
 * Iron Man 3
 * Ant Man 2
 * Hulk 2
 * Black Panther
 * Guardians of the Galaxy (not part of the Avengers)
 * Avengers: Age of Ultron
 * Winter Soldier (introduced in Cap 2)
 * Falcon (introduced in Cap 2)
 * War Machine (introduced in Iron Man 2, but didn't join Avengers until now)
 * She-Hulk (introduced in Huk 2)
 * Guardians of the Galaxy
 * Star Lord
 * Drax
 * Gamora
 * Rocket Raccoon
 * Groot
 * Adam Warlock
 * Yondu
 * Nova Corps (intorduced in GotG)
 * Nova

Phase 1

 * The Amazing Spiderman

Phase 2

 * The Spectactular Spiderman
 * Black Cat
 * Silver Sable
 * Venom
 * Sinister Six
 * Spider-Woman

Phase 3

 * Venom 2
 * The Ultimate Spider-Man

Phase 4

 * Superior Spider-Mann
 * Scarlet Spider

Note
Namor and Man-Thing were brought back to Marvel from Universal Studios and Lionsgate respectively.