Refined speakers in a room full of mirrors will sound unlistenable.
So the only thing you can do is get a speaker that mulls over some musical details, like the acoustic suspension boxes that used to be fairly popular in the 60's and 70's.
You STILL must get a throw rug and some drapes, etc. to reduce reflections in general. Get the speakers off the floor and put them on some sturdy stands. Use putty or blu-tank to fuse the speakers to the stands. Of course this is an arrangement for a system that's used to play (mostly) popular music or rock. But they'll produce strong mid-bass and pleasant mids.
As for hight frequencies, you WANT a roll-off so your ears don't hurt.
Your entire chain should be unexceptional (but still have some refinements). I'm reminded of an acquaintance in college who played Deep Purple (LOUD) in his dorm with a larger-than-average pair of speakers,
The album sounded pretty good to my ears, so I had no complaints.
After all, MY stereo at the time was a reel to reel with built-in speakers.
OK sound, but without money I imagined it was "magnificent".