I use a free program called colorjive.com. Can rally only do more saturated colors over light colors, not the other way around. But also, these colors are only representational and do not at all represent the actual color chosen. That is a SW color, tan, for example, don't know which one, but it would look very different IRL than the actual color. Do you have a brand preference?

I would just stick to white cabinets for it all. That soapstone is beautiful, and white cabinets give it the best contrast. Plus, white and black is a classic combination. Dove White should work, just ask for a sample cabinet in that color and hold it up to the stone you want to make sure you like how it looks!

What color maple? Top? Flooring? Help us help you.

There are endless combinations. Have you looked at inspiration pictures of kitchens that resemble yours and what you are drawn to, colors and usage. Light or dark counters are also a personal decision and hopefully research will help you decide. Big decisions. Do you have an island and if so, you could use a different countertop for added interest. I think this island is poured concrete.