I'm pretty sure Corian doesn't have trouble with scratches on dark colors anymore. They are solid all the way through. I love Corian. Here's a tread about Corian that someone started a while ago. Lots of opinions, pros and cons. It seems that a lot of people love it. https://www.houzz.com/discussions/corian-scratches-dsvw-vd~5062035

Keeping the countertops the same ties the island to the wall cabinets, especially with the colors being so completely different. We did a wood island with white wall cabinets as a display in our showroom, to show a variety of finishes and color schemes. However that is not typically what clients want in their homes. Unless the second color is very similar to the first it will look too haphazard. Cambria shows two different products here but they are so similar they blend well together. Generally we see more kitchens like this, with the same countertop throughout. Best of luck!

We went with Sherwin Williams Oyster White! Not pictured in these pictures but I’ll snap one. It contrasts well with the white trim and white of the cabinets

Thanks for asking Kerrica. With the pandemic, we have been in limbo. Our bathroom is torn apart, prepped and ready to go as soon as things open up. We've decided to go with Taj Mahal quartzite for the counters and a "wood" porcelain tile for the floor. We want to extend the floor tile into the shower with a linear drain. I have to agree with others that, if we go with a natural stone for the counters we should go with a natural stone in the shower, However, I'm having a hard time finding something that goes well with the Taj. We're thinking of using large tiles to avoid too much grout. Slabs for the shower seem too expensive and have too many installation problems. Any suggestions on shower tile would be most appreciated! We are open to other flooring options if it would go better with the shower tile.