With it being populated, it does limit your good guys like Supes, Hourman, and Black Panther. Balanced by your villians that don't care, Deathstroke, Maestro, & Kang.
Deathstroke / Black Panther: It'll run quite a while thanks to Challa's intelligence, tech, and more importantly, Vibranium. Deathstroke wins but he'll be in no shape to help anyone.
Hourman / Kang: Like Blaze said, Kang's tech is lightyears beyond anyone else involved in this match. The real point here is having a Master of TIME take on Hour man with TIME limitations. Can Kang's abilities forward Hourman into being obselete? If so, then Kang and if not, Hourman.
Superman / Maestro: There is no greater Hulk, even Scar, in my estimation. His intelligence dwarfs Supe's and Clark's no dumbass. His raw power is more than enough to knock Supes out but he won't be able to hit him IF Supes uses his Speed. Superman rarely ever does though, so it's a slugfest and that's the worst possible situation for Superman considering the insane healing factor of Maestro.
This one favors Maestro because Clark HAS to hold back from anything too drastic that would kill innocents and Maestro has no such restraints. It's as close to a Doomsday situation as you'll see. It'll go for longer than any of the others, but I'll take Supes 5.5/10.
DC Team emerges beaten and bloody but victorious.