I just spent a few hours rereading Nu52 Batman/Superman
My main takeaways are that Jae Lee and Ben Oliver totally kick the art out of the park during the first issues, and I wish I could read more of the older (Earth-2?) world. I know they eventually got Darkseid' to pieces (and then there was a very long and silly migration and whatnot I only sort of followed), but I think TPTB made that happen because Batman and Superman had sort of won.
But mostly, the art was gorgeous; moody, strange, dramatic. As an example, here's Bruce Wayne (in disguise) sitting in a park bench:
It's all like that. The perfect style for that pair of over-dramatic prima donnas (in all fairness, everybody and everything looks over-dramatic drawn that style).