Justice League Will the first JL film be the closure of a trilogy or leave unresolved plot threads?

[Lord]

So, the film supposedly starts shooting today, and it seems like it will proceed with Zack Snyder on the helm. The film might end up being as badly received as Batman v Superman and if that happens, it could be Snyder's last film in the DC universe, so the question is: should it close the Darkseid storyline?

Terrio said that it would be the end of a trilogy started by Man of Steel and from what i heard (not something i'm completely sure though), the original script for Batman v Superman mostly had references to Brainiac instead of Darkseid. While they don't need to end all of the New Gods storylines, i feel like the film should on the very least give some closure to it. Darkseid's invasion could be stoped, and he could "seemingly die". If Batman v Superman was compared to Empire Srikes Back, should Justice League One be a sort of Return of the Jedi? Or should it be more like The Avengers films? Where the next threat is constantly being hyped up?

I myself would like to see it serve as a closure for Snyder's trilogy. Even if he comes back for more after this, i think it would be better to give the JL film after this enough "Room" to be something different. This way, if they want to bring in George Miller, he can proceed with a similar film to what he originaly wanted to do, or if Snyder wants to return with something similar to the "Crime Syndicate", he can do so too.

That said, Dawn of Justice hyped up a lot of plot lines that might end up being too difficult to tie up in a single film.

So in the end, should Justice League One be a conclusion of Snyder's storylines that doesn't leave "loose strings" to tie up, or should Darkseid's invasion be given more than a single film?