Looks sweet!
My predictions:
1.) Movie will be good. But will be a dead end, that doesn't affect any of the other movies, since they're resetting everything.
2.) Michael Keaton will be Batman, we know. It would be cool if he was Thomas Wayne, and the time travel allowed Thomas to live and Bruce to die. But this is modern day, so we can't have smart writing, so its probably Bruce.
3.) Henry Cavill superman now dead, this is his cousin, Supergirl.
4.) Other Barry Allen will go evil, either become Reverse Flash or Black Flash.
5.) Batman will barely appear in film, mostly be what we saw in trailer.
6.) Probably other Barry will try to go through time to undue some characters dying, so main Barry will see why this was wrong, and stop him.
Will do fairly well, but not break even, because of all the reshoots and delays. Will be regarded fondly in a few years as a cult classic, especially when it is reset.
That's my prediction. Y'all?