I think white subway for a backsplash is perfect. One with a matte texture would be nice. That dark grey is really closing in your space, I'd consider painting a much lighter shade.

I agree with adalisa frazzini. A light colored mosaic would go perfect here. It would give you just a touch of color to your white and gray kitchen.

We definitely are considering a shade 50% of the current shade. What color mosaic, anything you've seen that looks good?

Something such as the tile above from Lunda Bay Tile might be a good option for you. We have used their products quite often and have been quite happy.

Couple of fun options from modwalls.com

kind of like these, or the 2nd one above from dclostboy if you’d like to add a pop of color too

Backsplash Tile Ideas · More Info

Kitchens · More Info

With a small space, assuming it isn't your forever home, use accessories for the trends and unique features. Keep the permanent installations elegant but adaptable.