Need Help Designing a Dream Room

The company I work for got acquired and I'm moving to the new headquarters in Charlotte. We're having no luck finding an existing home meeting our unusual needs (smaller house since we are almost empty nesters, but big listening room on the first floor), so we're building a new home. Hot dog! I finally get to design a dream room!

I'm not an audio engineer, so all I know (and it might be wrong) is that one should use the 1.618 ratio rule. Therefore, I am planning on a family room which is 11x18x29 (nothing is set though). The floors will be hardwood (my wife, who is generous, gracious and loving enough to go through this process instead of buying a perfectly fine regular house, insists on the flooring). I have very large speakers: Montana KAS's. I love many kinds of music: Jazz, blues, classical and rock.

How should I design this room? Separate electrical box? Dimensions? Materials? Rounded corners? This will open into the kitchen and eating area (separate rooms) so we can enjoy the music there as well. Thanks in advance. I look forward to your advice.