In theory if they maxed out their shit and went full Goblin Slayer, Batman, Cyborg and the Flash should be capable of delivering world peace and global utopia.
Batman has the ambition and determination.
Cyborg has the intel.
Flash is the boots on the ground.
How is Batman's relationship with Cyborg in rebirth? If they ever started working together more they could achieve a lot. They wouldn't even need Superman or Wonderwoman or the GLs to achieve global peace and utopia, and to snuff out all the sick shit on the dark net. The GLs and Supes and Shazam and Wondy would be able to deal with all alien threats, and Aquaman can protect the oceans lol.
Get your shit together, justice league.