Typically most speaker manufactures design there products (in their test chamber) to be relatively neutral (with a flat response) or a touch warm (with a slightly descending curve toward the high frequencies). If your room is truly reflective and reverberant you will benefit from having EQ at your disposal to help balance the system a bit but that won't solve the reverb. I suggest looking into a high quality DSP/Room Correction unit. They can compensate, to an extent, for reflections and have almost infinite EQ. . At the last show we did, CAF 2022, we were in a ballroom that measured 35" by 50" by 12". It was too massive to consider passive room treatment. Hard walls, huge room, I had never applied room correction to a room like that. Most people's impression of our system's performance was very positive. The RC unit worked better than I expected. An added benefit to these types of systems is that you can create several optimization curve for different listening and toggle from one to another on the fly.
Controlled dispersion line arrays with DSP/RC would be my suggestion for that room.