Great post! I've been re-reading old Legion stories in order (up to just before the Baxter series launch now), and what's really interesting is the letter columns. You can see how active the fandom was, and how that impacted the stories in so many ways, from voting on Legion Leader (a GREAT concept, I wish they'd bring that back somewhere, gave you great WTF twists like Dream Girl's win), to the various fan names worked into the story in wink-nod moments (see real names of Lamprey, Crystal Kid, Nightwind, etc), to the different fans-turned-creators like the youthful Jim Shooter, Paul Levitz, Tom & Mary Bierbaum. It was really cool.
On another note, I still get a kick out of the fact that LSH basically sidelined Superboy in his own book to the point where they took it over completely. lol