Massive What If...
What if, for any number of creative and economical reasons, DC and Marvel had merged early one in, back in the QC and Timely days, all our favorite characters have been invented but they all are contained within the same universe. What could this have lead too? How would some characters be different?
For some reason, I'd like to see Batroc as a younger guy, and have him and Nightwing be friendly enemies. I think their skill sets are similar, and would love to see a story with them clashing, like Bruce sends Dick away to some university in France, and he meets up with Monsieur Georges Batroc, fresh out of the Foreign Legion and prodigious master of Savate.
Also, Black Adam and Red Norvell cavorting around on metahuman bar night would be sweet.
Who would they add to the JLA, the Avengers, Thunderbolts, JSA, Invaders?