I was thinking...
Green Lantern Vs Sinestro
Wonder Woman Vs Cheetah (maybe?)
Superman Vs Mr Mzytptlk (only because I saw a comic with all the existing might Micros DC LEGO sets and him in it. After all he is he equal of superman, something like that anyway)
Then later on
Aquaman vs Black manta
Supergirl vs brainiac
Any ideas?
Thanks Captain Britain!!