green is a nice compliment. these SW greens are a good starting point.

Lucky you for all the natural light.

It's just my opinion but I would take a different direction.

Keep the cabinets, flooring & countertops as is.

I would find a better backsplash to complement the countertops

Repaint the walls. Add some wall decor that has black accents

Change out the fan to a chandelier in black

Make sure ALL the appliances are SS and reduce the depth of the fridge that is sticking out.

I also don't think there is anything wrong with the floor, although maybe the picture doesn't show it well enough. I would never go lighter on a floor because it just shows dirt better. I am not interested in having to wash my floor every day. So I agree with Beverly, and Lyn is right, greens look good with cabinets like this.

Different wall paint, replace backsplash, single bowl sink either with or without replacing counters. Low profile under cabinet lights & remove the clunky light rail. Looks like the overhead lighting in the kitchen could be improved upon.

...plus adding in a custom White Island.

Would rethink this. Looks like you will be erecting a barrier island and a white island is going to stick out like a sore thumb in this kitchen.

Flooring looks fine. If in good condition, you can add a runner to infuse more color. If you replace the flooring, I would not go lighter.