Room acoustics are key for ALL music, maybe even more important for simple music. Try listening to a solo piano in a reflective room, like cats fighting. Do you think a Norah Jones recording would sound better than the 1812 Overture (Lone Ranger theme) in a bad room? No.
So, you get the room right. There is STILL a difference between simple and complex music in a good room that is a problem.
I completely agree that the speakers have to be matched to the room to resolve the problem of complex music presentation. I agree with many of the work arounds presented like the big full range speakers @jayctoy uses, I also agree that quality electronics are important as the speakers can’t produce a signal they don’t get and it will sound mushed coming out. When I am listening to complex music I can send the stereo signal to my Sony Signature DAC which remasters the signal in DSD. My processor then upmixes the signal for my 9.2.7 speakers. I just listened to Bach’s Brandenburg Concerto streaming on Stingray Music through Plex tonight. Not a full scale orchestra but not a quartet either. It lifted me right into the hall they were playing in.
Now, I sometimes will set my X-Box Series S to output in other formats. The other night it was Michael Buble with a HUGE big band recorded in Vegas streamed via Qwest TV on Plex. I set the X-Box to stream it in DTS 7.1 then upmixed it in my processor to 9.2.2. Fan f----tastic. The audience applause envelop you like you are there. The DTS renderer in the X-Box and the DTS-Neo-X upmixer in my Marantz processor layout notes and instruments in a way I have never heard in two channel with both dynamics and precision. For my taste in a complex music presentation wide channels are key, much more so than height channels.
You get the idea. This is the youtube version of that video: