Nice concept for a Home Theatre system.
In addition to the other good questions just posted above, I might also ask if you are considering the merits of a HT PC (computer ) with MCE capabilities included in your HT system ? This provides the opportunity to work on the computer, display downloaded music and movies, N.MUSIC, N.RADIO, etc. ( with a Beoport PC ) and also gives you a second DVD and HD drive to use.
We use a Beosound 3200 as a HT system master, with BL 4000 front speakers, and BL 4 rear speakers. The BL 4000 are sitting adjacent to the BS 4000 as B&O intended, but the BL 4 pair (after some sound trials ) were ultimately attached to the ceiling. The latter came as a suggestion from a B&O store owner, and given the improved sound, proved to be a very good idea. Note also these units are all hard-wired through the house, and connected using the B&O Master Link cable system.