One thing (among hundreds of things) I don't like about Justice League - and Snyder is a guilty party - is the exclusion of the current Green Lantern. They're charged with protecting inhabited worlds.
One explanation, as I understand, is that Earth seems fit to defend itself. After all, the humans, Amazons, and Atlanteans all defeated Steppenwolf after that GL was killed. John Stewart would've made the movie much better in place of Cyborg. And I do like Cyborg.
Either way. I'm still 'praying' for the Snyder Cut...