Furniture, Wood and Cabinetry Finishing - different wood finishes

Okay, the great room, we are going for a formal look. I painted, did a faux treatment, love it! I was going to refinish the window and door trim in a dark mahogany to compliment the furniture I planned to use, but now I LOVE the way the paint looks with the existing dark golden oak. I still want to use a couple of dark mahogany pieces of furniture, (an armoire for hidden entertainment components, and an almost dresser looking buffet/credenza thingey for blanket and decor storage,) but now I also have a couple of wonderful round claw footed coffee tables that were my grandmother's that I would like to use. I have no problem mixing wood finishes, I think it makes for warm and inviting environment, but not really a formal one.
We were also planning on putting up a chair rail, (DH likes lots of decorative trim work) which I have already stained dark mahogany, to match my window & door trim, WHICH IS NO LONGER GOING TO BE dark... :eek: Would a thinner piece of trim run along the top or bottom of the chair rail, stained a dark oak to match the window trim, bring the wood colors together? And what, oh what, should I do about the crown molding? Right now, the baseboards are the same dark oak as the window trim, should the crown molding also be? Any mahogany there at all? Should only the chair railing have a mahogany accent? AAAUUgh!! My husband also plans to try his hand at some minor carpentry work to build a couple of square column type things and a cornice to frame one set of windows; that will house our front projector screen when it is rolled up. These columns and the cornice could be any finish, or a mix of the two. Help please!!

See duplicate post in Decorating & Design forum for replies. :)