To be clear, I don't go for a flat curve, but one that best follows the general trend of my room. My main point is that I don't think it's a good idea to iron out every peak & trough until it lies right on the target curve - some leeway must be allowed to allow them to "ride" the room's natural ebbs and flows, to keep it natural. (Ooooh, listen to me.)
JRiver v25 (Windows) >> 220Pro/CI >> PMC Twenty5.23 + twin KEF KC62 subs. One White Phantom.