Ever consider hosting the av rack outside the theater, and move the entry door over? Now you have uninterrupted side walls, if you elevate the av rack, and
simply use the area beneath to be access to the back of the rack. The rack could elevation could be as simple as floating it across 2 pieces of steel angle iron,
supported by 2x6, on the side walls.
You actually could create a small bit of wow factor with a small section of feature wall of some sort, embed a hdtv for a digital movie poster lightbox, and tie in the
av rack with the entry door. You also could do fabric side walls, with uninterrupted side wall, and easily run conduit from the av rack, to the front of the room. It also
eliminates one door in the theater. That little extra bit of detailing outside the theater, also might let you go a little more hard core and push for better audio and video
performance in the theater.