So with the Harley Quinn show putting so much effort into getting her into the Legion of Doom (I haven't seen the Aquaman episode yet), it's got me thinking... The League more or less has the core 7, but what about the Legion of Doom? Is their most iconic lineup out of the Super friends, the Doom film, Harley Quinn, some lineup from the comics, or something in between.
Personally, I like a legion that parallels the League of the time, but that doesn't HAVE to be just archenemies. Joker not being in the mix in favor of Bane or Riddler works as well, for example. It just depends on the goals of the legion for that story.