The thing with Green Lantern, is that it was originally done by the very guy that is now doing DCTV on The CW, but much like with BvS, SS, (
and supposedly WW as well ) the studio came in and made executive decisions about the direction of the film, therefore making drastic changes to the script.
Apparently the original script was much better, but the studio wanted a GIANT enemy event at the end, but really just messed up most of the movie and left us with that mess.
Luckily Berlanti found his success on TV and the movie division continues to be a hot mess.
Actually, until the most recent change with WB/DC to get a Comic guy at the top to oversee their cinematic universe direction, They wouldn't even allow the comic people to be involved in the movies at all. When they should have been tapping the then excellent Animated DC storytellers to give original script treatments to the movie people, they blocked them out, citing that they don't know anything about movies or something ridiculous like that.
I'm hoping that if DC takes anything from the outline Marvel has laid out, is that they not only lay out an actual plan, but hire someone to make sure all the movies stay on the path (for continuity reasons). and let the comic people, you know, the people that actually know the characters you're making movies about, deliver script treatments, and just generally be involved in the movie process, so we get good, faithful to an extent, characters in good movies that make sense as a whole.
Right now the DCCU is a mess, and they seem to be creating the path as they go forward, crossing bridges as they get there.
This would have made sense for Marvel to do 8 years ago, as they were trailblazing this approach, but even back then they had a general plan laid out. They just weren't sure if they were going to be able to execute it all, since they were a brand new studio tied a company with history of money troubles. DC doesn't have that excuse as they've been owned by WB forever.