I would a full splash in some exciting tile.
You could complement it with a painted ceiling and a more interesting lampshade

Since you already have the short granite splash, I'm not sure I'd add a tile splash above it. Maybe just paint the kitchen a color you like. It's a nice kitchen.

I would paint or add a colorful back splash that ties in to the colors of rooms adjoining it. The add a light fixture that has more interest. Add some colorful curtains and counter canisters etc it will feel more colorful and inviting. Add some plants faux or live will breath fresh air into a room and looks good with everything.

I would paint the walls with Farrow and Ball Green Apple. It would look great against the dark cabinets!

Good bones and any color you love would work if you accessorize correctly. What is your style? Is the light centered over the island? What are your plans for the window? Will you be setting things on your counter or do you like everything behind doors/ You need to line all these up before you choose paint.

A fun colored backsplash would bring color into the room.

If you add a tile backsplash, please look at lots of Houzz examples of tile splashes above short granite splashes. It's important they work together well. In these two examples, I like the way the first works (although I would have skipped the decorative rectangle over the sink) but I don't like the second. I think the splash fights with the granite and it's even more obvious because of the short granite splash.
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I would choose a collorfull backsplash mosaic (orange or green) and a kichenaid mixer. Maybe a colorful light pendent too.

I would suggest painting the walls a bright nice color and add a fun light fixture.

You have a "neutral" palette to begin with, so select a color that you enjoy and paint both above and below the cabinets.

Add pendant lights over island...add texture tiled backsplash...add 2 ball topiary on either side of window...paint soffit ...add roman shade above window...counter stool at end of bar. Sometimes its not all about color as much as it is about layering texture.

I would add 1 or 2 rugs/runners to the floor. Find one that you LOVE and simply paint the upper backsplash and fur-down with a complimentry color to the rug. You might want a simple window treatment to tie it all together, like a roman shade, etc.

I would also put a ceiling fan (without a light) where the existing fixture is and add can lights. Seems that single light in the center is not going to be sufficient task lighting.