Doug: Whaddaya think? The Justice League of America, the Defenders, the Forever People, the Avengers, the Challengers of the Unknown, the Fantastic Four, the Legion of Super-Heroes, the X-Men, the Secret Society of Super-Villains, the Champions, the Justice Society of America, X-Factor, the Teen Titans, the Invaders, the Doom Patrol... and on and on. There is certainly no shortage of strong nominees for your favorite book of long-john buddies (yeah, that sounded weird).
Of course, being a teacher I'm not going to let you off the hook with a simple answer -- puh-lease tell us why you feel the way you feel. And have a blast doing so!