It looks very similar to our kitchen and we love it. For color - throw in a few colored rugs; a colored bowel on island; colored tea pot on gas oven; could add a few cabinets with glass doors and that gives you the opportunity to put some color behind them. We purchased our house with the ”taj mahal” quartzite and we’ve grown to absolutely love it. One small change that made a big difference - added brass knobs and door pulls which really dressed up the kitchen. Hope that helps but our kitchen is not ”boring” - nor is yours. It’s elegant in its simplicity. We love your dark island with white cabinets - we have the same thing. Last - we did add some dark beams on the ceiling above the island which pulled everything together.

Fabric covered stools will add some color to this beautiful kitchen.
Here are some ideas.

Or textured ones.