I'm not really active in the fandom since I'm so behind on movies (haven't seen Infinity War yet), but Guardians of the Galaxy is probably my favorite MCU movie. I mostly came out of it shipping Peter/Gamora and not finding the fic to my taste, but I remember liking the Guardians poly and gen stuff more. I loved Yondu, so I had fun with some of the Ravagers fic, but it was so popular that it got eaten by terrible fanon pretty quickly.