Leaving the lovely wood floor as is, I would paint everything one color...walls, ceilings, kitchen cabinets, stair risers, (but not the treads because those relate to the flooring),railings:

B.M. White Dove is a safe choice. Ceilings, flat finish, walls, eggshell finish, all trim in satin. You will have one color, but the finishes will provide depth and the rooms will flow together, with none of the stained wood trim outline.