Antman is the epitome of superhero movie done right, imo. Extremely light, fun movie to watch with a compelling plot and interesting characters. ;o

But, in terms of grimdark, I've read the first two issues of Extraordinary X-men and they've been heavy on the dark side, especially concerning Wolverine's past. (but that's to be expected, Logan's always been a grimdark character, though I enjoyed his stint in Japan)