Here's what I know about the thinking at DC Films these days: Superman is a priority. The character has been wounded in recent years by Man of Steel and Batman v Superman, and the folks behind the scenes want to rehabilitate the Man of Tomorrow. They want to fix him, make him less mopey and less unsure of his place in the world. They view his upcoming resurrection in Justice League as sort of a soft reboot, an opportunity to right the wrongs that have been done to the Last Son of Krypton.
That new version of Superman will also get a chance at a solo adventure. One time fanboy maven and now trade journalist El Mayimbe reports at The Wrap that WB is moving into active development on a Man of Steel sequel. That's still early days - they still have to figure out stuff like 'the story' and 'the writers' - but it indicates that WB is still dedicated to this character.
Here's the rub: WB has also shown themselves to be highly reactionary when it comes to Superman. Their mistakes with the character on film in recent years have all been examples of over-correcting; when people complained that Superman wasn't heroic and physical enough in Superman Returns they had him level a city in Man of Steel. When people complained he caused too much destruction in Man of Steel they made him hated by people in Batman v Superman, and then killed him off. I hope that they don't overreact to our critiques of Superman in that last film, and that they find the right mixture of goodness and punching shit to make a good Superman movie.
My pitch? I'd use Metallo or The Kryponite Man. I'd find a villain that Superman can battle physically while also being heroic; both of these guys emit Kryptonite radiation, so Superman would be robbed of his powers in their battles. You'd have a chance to see Superman use things other than his super powers - his smarts, his wit, his decency - to take down the baddies. His sacrifice in BvS doesn't read to me, because he does it all for Lois. A weakened Superman risking his life to save a child from Metallo is much more Superman to me (note to screenwriters: while it's nice to have Superman save his friends and loved ones what makes him Superman is that he saves all sorts of innocent people. Those are his stakes).
At the very least I hope that WB finds a filmmaker who understands Superman, who accepts that this guy is a hero through and through and doesn't feel the need to deconstruct him in an attempt to figure out why he would bother helping strangers.
I am allowing myself to feel hope about the DC movieverse, post-Suicide Squad. I hated the film much less than others, but I think everyone can agree that WB stepping in to do stuff like remove mentions of Slipknot being a serial rapist is, at the very least, a move in the right direction. Now with Geoff Johns - a guy who I think gets Superman - in charge maybe something good can finally come of the latest big screen incarnation of the Man of Steel.