Yeah, the contrast of the color palette is not great right now. I started off trying to hit the "use only five colors" diversifier, but it's just not enough. I still plan to use a (tinted) grayscale for the most part with color used very sparingly for better effect, but it'll be more shades of gray for sure.
I like the mist idea! Effects like that are not something I have experience with, but it's worth exploring in the polish stage.