I agree the dark grey trims look great. My suggestion would be to introduce a different shade of color to add some interest to the exterior.

There is a lot of red in the stone, so when you introduce a gray, make sure the undertone coordinates. Choose a warm gray. Steer clear of cool grays and yellow undertones on the exterior because they will not look good with the red in the stone.

Another trick to break up the verticals is to paint the lower half of the house a darker tint and the upper a lighter tint of the same color. Love this blog ( http://www.mariakillam.com/) for advice about undertones and paint color.