I love my particular solid surface but would have opted for quartz if builder would have done it. I say quartz for counter and any number of choices for backsplash.

We've had corian in the past and found it scratched too easily. We have a quartz countertop and backsplash now (Bianco Drift). Coordinating tiles are an excellent option as well.

corian scratches can be buffed out with the correct grade of 'plastic pads,' even burns

I would still choose quartz for countertop and then reassess backsplash.

Thanks all! I was thinking the quartz as a backsplash would be a nice vertical element to tie the maple cabinets and stainless, but I'll reconsider using it as a countertop. Now I have no clue what color or type tile as a backsplash would complement the quartz countertop and maple cabinets. Maybe a warm cream or soft taupe-grey (matte rather than glossy)?

I would pick the quartz you like and pull a color from there. I'd look at a textured mid grey or deep green. The pics are from the internet. Have a look at Caesarstone Stone Grey. The color is different in person than it is online.

I think you could use your chosen quartz as backsplash, and a matching solid gray as counters, or use it as counters and get a simple gray or white tile as backsplash. Either way, you'll get to look at the stone you like, and it will tie into your cabinets nicely.