Alex Ross did a "grounded in reality" redesign pitch that didn't get picked up (but later used in one of the Earth X sequels) and I always thought they looked really inspired in their simplicity. Although some of these characters aren't going to be in the movie or it's future timeline scenes, I like the idea for a dystopian future. The dark costumes and hoods/capes fit in perfectly with the idea of rebellion and lurking in the shadows.
I LOVE Angel's costume and how he's meant to disappear when in the sky. And Jean's skirt overlapping the boots was supposed to be a throwback to the Phoenix costume. Logan's would have to be made more movie friendly (since it looks like a jumpsuit hah!).
These were inspired by X1 with the black and colored accents. I would want the costumes to be more intricate in the movies, but I think they're a good start!