Question about comic book characters?

I just need some advice for a diorama i'm putting together. now obviously the joker and batman are arch enemies, and green lantern and sinestro as well. what i need help with are superman, the flash, and aquaman. now with aquaman i'm pretty sure it's black manta but i could be wrong. superman i would say lex luthor, but i feel there are others like darkseid who might fit the bill more. and finally with the flash it is between professor zoom and captain cold. any feedback at all would really help.