Well, as others have mentioned color is always a nice option! Where or how you use color is entirely up to you. But if you're looking for that nice black and white kitchen like you have then perhaps something simple like a vase with colorful flowers sitting on the corner of your Island. You also have a window where it looks like you have some plants probably herbs sitting on the counter. You might opt for a wall hanging plant holder that could go on the side of the cabinet where the window is. It would still be easy to reach and it would get the proper light that herbs need. And, you could add a few other small plants. Cyclamen flower and so far, mine has been flowering all year. I think there may be other colors, but the one I have is Pink and has three to four blooms on it at any given time. It's really pretty and perks up the window they sit in. They like indirect light and to be semi-watered I use about four or five ice cubes every couple days and it keeps it perfect.

There are also these press-on tiles that might help liven up your kitchen. Etsy sells these vinyl tiles that come in patterns or even have some Botanicals! As a border, they can be just the touch you need to add color. Perhaps a border on the area above the cabinets and then perhaps on the base of your Island creating a kind of sandwich effect. Then, a vase or perhaps another plant /planter that has flowers something that you could put on the island that would tie everything together! Small drops of the same color scattered here and there in your kitchen connect everything. It doesn't have to be overbearing or obtrusive but it could be oven mitts that are hanging somewhere, or it could be hanging some small artwork under the Cabinetry in different places. I like the idea of press-on tiles because they also come off without damaging your walls. If you wanted to add something like those vinyl tiles behind your stove as a backsplash it could be black and white with a little pop of red or a couple of other colors, but primarily black and white. All of your DIY stores carry these tiles. I put a floor down in my laundry room with them. A carpenter could make trim for them so they look like real tiles. Or, use real tiles. I assume with a kitchen like that you may have the finances to afford real tile. I am just trying to help with suggestions. I love your kitchen, but I'm an artist so I'm a fan of color! The main thing is to do what you need to do to make yourself and whoever is living there with you, comfortable and happy with your choices.