Marvel is doing dark and gritty better than DC...
The Netflix shows, Infinity War, and Winter Soldier are examples of how Marvel does gritty and dark and realistic takes on comic book properties and does it in a way that feels artful, genuine, and deserved.
DC's darkness comes from simpletons who think making ANYTHING super dark and dour immediately makes it of higher merit. It's this insecure angsty teenager mentality these middle aged directors didn't grow out of. And neither did the silly fans who say you can't be "adult" without it. It's not genuine. It's emo "dark." And it sucks the life out of the room.
Look to Marvel and take notes DC.