User blog comment:The S/Fan Stuff - Stay or Go?/@comment-995426-20150923050538

Keep all the quasi-official stuff. Kevin Eastman actually contributed to the Image TMNT conclusion.

As for other fan stuff, I think it's okay for user-submitted stuff to remain on userpage space (User:Username/Subpage, etc.). I don't have an opinion on stuff like "Darkness" I've seen edits for recently.

But Mutant Ninja Turtles Gaiden? Casey Jones fan film? Definitely keep all those articles. Not only have they become much more prominent than mere fanfiction, but the author of MNT Gaiden is totally okay with its articles and media being on Turtlepedia.