I think in order to distinguish him from Thanos, they should haveDarkseid do something badass. My idea is, Bats and Supes send Doomsday to the moon at the end of BvS, and in a post-credits scene, we see a hand effortlessly pick up a struggling Doomsday, and then a dark red force fry the crap out of him. His dead body falls as the camera zooms out to show Darkseid, in front of a Boom Tube, maybe with Desaad and Kalibak to either side, as he looks to Earth and says something like "This is what it takes to nearly defeat your heroes? ... Pitiful."