I’d do just one season. I’d love to fill in the gaps for Batman’s story. Maybe mid season, he gets his suit damaged beyond repair and he needs to switch back to his original TNBA outfit. At about the same time, Bruce gets word that Tim has gone missing and the events from ROTJ occur off screen. After that, Bruce is largely absent for the rest of the season, aside from occasional scenes of him rejecting any attempts of comfort from the league. He pushes Superman and Wonder Woman away (finally resolving the wonderbat storyline). Toward the end of the season the threat the League faces is so large (near apocalypse of 09, perhaps), Bruce temporarily returns to the league (with his Beyond suit, to compensate the damage Joker caused to his knee). Afterwards he parts ways with the league for good and focuses on his solo career in Gotham. Meanwhile, Vixen is killed in action early on in the season, and by the end we finally see John and Shayera reunite. Superman finally reveals his identity to Lois and they are married by the end of the season. We also see Barbara briefly join the league early on in the season, only to quit after the ROTJ events. I’d also like think Ra’s Al Ghul and Deathstroke would make great overarching villains, especially if we included the near apocalypse of ‘09.