Are you thinking of painting all the trim darker gray? Yes, I have painted walls, (not gray) and all my trim, and doors and baseboards are painted black. You can paint them any color you want to, but, it looks better if all trim and doors are painted the same color throughout the entire house

I would say the same thing as cat. Keep the trim and doors consistent, dark or light both work depending on your taste.

Baseboards, all trim/doors one color, but don't have the walls too dark... Keep in mind that your trim and doors need to be special..otherwise, why highlight them.