Running cables for a home theater: inside walls and ceilings or on the surface?
This problem is most easily addressed by surface mount wireway. Rather than run exposed cables, you attach a fairly innocuous plastic or metal rectangular cross section wireway/duct/conduit that carries the cables across the ceiling and/or wall in a less obtrusive way than putting them out in the open, but which does not require major surgery to the building to install them. While you evidently don't like the ones you have seen so far, there are many options at many quality and appearance levels, so there may be hope that you can find one you like. Or get all 1970's retro and attach some hollow fake beams to the ceiling.
Where more convenient, there are also similar products made to go on the floor, typically with small ramps on either side so they are less of a tripping hazard.
Adding some sizable crown molding all around would be another approach to create hidden surface wire space along the edges of the ceiling, if that suits your taste better.