Re: Fighting Reflective Rooms Through Speaker Placement Angles
So can you move the current speakers, even if only temporarily? Why not rehang/reaim the current speakers in a center cluster configuration? Horns may need to be rotated, and you are still going to get some reflections off the walls, but simple physics dictates that by reducing the number of sources you will reduce the number of reflections.
Front fills would still be a good idea, even if only to bring the imaging down in the front. (Does the central equipment pool have any of those Control29s laying around?)
It appears that the original "designer" (and I use that term loosely) attempted a "stereo" installation in this room. Given the acoustical challenges, and the scaling challenges of stereo (see Bob McCarthy's blog here for a much more in-depth explanation), you would be better off with a mono center cluster application. They still may be the wrong speakers for the job, but with little to no budget you play the cards you're dealt.
Also - any extra pipe and drape laying around? Even schools sometimes have a couple extra hampers of drape that could be useful.