I'm thinking BM White Dove for the walls since everything is dark. It's a soft white with grayish hue to it. I would use it for trim also.

It would be helpful to see pictures. We would need to know the style in order to suggest BS.

I used White Dove for our guest room walls and painted the ceiling and inside doors RH graphite. I'm not a white wall person but it looks great.

I was going to suggest a terra cotta color. How about using the same as your dining room?

I also like yellow with gray. Not a screaming lemon yellow, but a more subdued goldish yellow, almost mustard. Sorry, I don't paint, so I can't suggest specific paint brands/colors.

Here's my backsplash, which I chose to coordinate with my slate floors, cherry cabinets, and black/gray counters:

{{!gwi}}

It's a combination of slate, black glass, and stainless steel.