I have a linen colored Corian with a sandwich black color in my kitchen. My appliances are black. Seventeen years later it looks like new. I also chose a beautiful sage green with flecks of cinnamon for the master bathroom. My vanity is natural cherry. Both look lovely. What sold me on Corian was that you can buff/refinish them in the event they get scratched.
I have a custom made granite dining table in the kitchen. It is lovely but I don't think I would pick granite for countertops.
I think you need to hit a few kitchen places before you make your decision. There are so many choices and you need to know which one speaks to you. Good luck and have fun! LM