Just recently finished watching the Marvel films in the Spaghetti order; which follows the logic that if a post-credit scene in a Marvel movie alludes to another film, you should watch that film next.
Iron Man (2008)
The Incredible Hulk (2008)
Iron Man 2 (2010)
Thor (2011)
Captain America: The First Avenger (2011)
The Avengers (2012)
Iron Man 3 (2013)
Thor: The Dark World (2013)
Guardians of the Galaxy (2014)
Guardians of the Galaxy Vol 2 (2017)
Captain America: The Winter Soldier (2014)
Avengers: Age of Ultron (2015)
Ant-Man (2015)
Captain America: Civil War (2016)
Spider-Man: Homecoming (2017)
Black Panther (2018)
Doctor Strange (2016)
Thor: Ragnarok (2017)
Avengers: Infinity War (2018)
Ant-Man and the Wasp (2018)
Captain Marvel (2019)
Avengers: Endgame (2019)
Spider-Man: Far From Home (2019)
Part of my reason was that I finally took the plunge and upgraded my old LG Plasma to an LG OLED, which seemed a perfect excuse for immersing myself in some 4K, HDR and Atmos.
The continuity in parts is very well done and easily missed when watched years apart. Overall I'd give it a 9/10.