The Super Boy movie is the first step into an actually well thought out and planned out Superman movie.
There are a lot of reasons that Superman as a concept and as a movie has not succeeded and the most important reason for that is scale. We have no way to gauge or even relate to Superman's power. But Super Boy is different, right off the bat he has a huge power nerf in comparison to Supes, he is a half human and half Kryptonian clone named Kon-El or Conner.
The reason that a Super Boy movie will work in mind blowing proportions is because we can start him off with very limited power and slowly bring it up as the movies progress until we finally have what I like to call The Real Superman movie. We can actually have our own Superman we can raise up Conner and have him really make us feel how difficult it can be to be Superman when you dont have all that power but you still have to bear the crest.
I dont know who they should fight or how the story should go I dont have much more than a vision really but thats what I see. I see a world where we let our heros broken or not return to saving us the best they can.