In addition to the other suggestions, if you can find them, Duntech Sovereigns or Dunlavy SC Vs or VIs could give you that big sound, but I doubt that the Luxman would be up to driving them to best effect in that big a room (especially the Sovereigns which, despite their relatively decent stated efficiency, really need an amp that can control their low frequency drivers).
If you really want to fill the room with your current equipment, I think Atmasphere's advice is the best; or else you can just use part of the room in a more nearfield setup as others have suggested, that would give you far more options. The glass walls will be an acoustic problem for you, I'm sure.
If you really want to fill the room with your current equipment, I think Atmasphere's advice is the best; or else you can just use part of the room in a more nearfield setup as others have suggested, that would give you far more options. The glass walls will be an acoustic problem for you, I'm sure.