Unlimited resizing and re-distancing windows.
Not to restrict how far you can make the windows go, or at least let us make it go as far as the biggest cinema in the world (probably 100-200 meters?).
Not to restrict how big you can make the screen go (otherwise, it would appear small if the distance is great). Or at least it should be larger than the max FOV (so about 180 degrees in the furthest distance would be good).