This will most likely happen. I'd also like a scene where it looks like Superman can't make a save in time and the Flash comes to the rescue.
Yes!!!! yes!!! i'd love a scene where Barry A rushes in, savesw the day, supes and the civilian look bemused and shocked, Supes asks him who he is, he looks as if to answer, then is gone. Then we see Supes catch up with him, he tries to talk to Barry, but due to physics of the speed it comes out muffled - that be awesome.
A justice league film should start in metropolis - lex luthor holds a press meeting - in this universe, the events of MOS have been in the past 4 months. Green latern events have just happened, but poorly covered up - it's all on youtube to see etc, also, a batman has been terrorising Gotham for past 3 years - Luthor uses these incidents as examples of space aliens and vigilante's - how they need to register and name these ''criminals'' form a justice league, a list of who these people are, to bring justice to them. Should they be disected like frogs as they are alien in nature, or tried like a common criminal - Bats.
This is a topic steeped in controversy, as the public are basically behind these people, but a few are wary!! Youtube and eye witness statements of the heroic deeds.
Luthor introduces a new form of drone, to protect the city - not these people.
Something appears in the sky, The electric grid crashes, like an EMP blasts major cities, drones dont work - everything is down, who do they call upon, all they can use is the list, the so called 'justice league'
Superman will have to pull as many people together to get them to want to help nations that no longer care.