By removing the microwave, I actually meant removing it and the cabinet above, and replacing with a stainless vent hood. Something like this pic, much more open and light.

Do you have under cab lighting? It really makes a difference at night.

That looks amazing! That's a great idea. Do you think the greyish/white subway tiles I posted will be too busy with the counters?

We just installed the under cab lighting and it definitely helps brighten the kitchen!

Looks like your countertop has more beige than grey. I'd stick with a light, solid color backsplash, rather than the varied shades in your example. There are so many tile choices available. Best idea is to bring home several and view them at all times of day. Best of luck.

Avoid another stone, so marble isn't a great choice in this kitchen. I also don't think a fancy shape will be any advantage, especially with contrasting grout. I'd go with a an elongated subway in a light color to coordinate with the lightest colors of the counter. You could do a herringbone design too.

Someone else with that granite used Grecian White large subway. It looks good.

Not large. I meant to 2 x 4 on 12" mesh.

Yes to what Anne Duke said regarding backsplash.

I would also consider painting your walls a slightly lighter grey and painting the ceiling the same shade but with half the pigment. We hired a color consultant for our north facing house, which felt way too dark when we moved in. This is what she suggested and it is amazing how much lighter our house feels.

And, your floor matts are rather dark and a bit busy. What if you had one long runner that was a lighter color without as much contrast?

Great advice so far! Your cabinets are really nice, so maybe all the changes you do make will help you avoid painting them. I agree a backsplash that's not busy would be the right choice, as well as a coordinating grout rather than a contrasting grout.

You will be amazed at the impact of under-cabinet lighting. Make doubly sure to choose under-mount lighting that is on the same Kelvin scale as the rest of your kitchen lighting, preferably in the 2500-3000 range. And don't choose a backsplash until you can view it that light, since the light may bring out certain tones in counter and backsplash you may not currently see.

I would change some of your cabinet doors to glass front, but avoid glass fronts directly around the stove for practical purposes . This is relatively simple and can really visually lighten a space. I also think it could help your sink and windows from feeling quite so closed in if you change some out in that area. Go for the least costly changes first to help determine the extent of more expensive ones. Oh, and have fun!