I can understand the frustration about the lack of dynamics of audio playback system vs. the real thing.
Last night, after coming back from nutcracker ballet, I listened to the same piece again at home and, while totally enjoyable, the magic of the concert really wasn't there anymore...
One place where it did not fall too much behind was the sense of space. For live recordings, it does seem proper mic placement and artful stereo down mixing goes a long way toward a realistic staging, even with supposedly hopeless headphones.
Another place that's really nailed is the tonality / texture of instruments regardless of the register they play in. As usual though, recordings are so much more detailed than the real event with the help of near field mics. Even though we were only few rows of the pit, there's so much non direct energy, the highs frequencies quickly get absorbed. Nobody would believe a home recording sounding that tamed down in the highs can be fidele to the real thing. To me, many classical recordings sound like if I was at the place of the conductor + middle of the hall at the same time so I get both direct and reverberant field in highly delineated fashion.
The one place where I felt my rig fell apart is the fortissimo indeed. I am so used to sound compression in the forte that I was surprised at the concert lol
. Coming back home, certainly I could not represent the sheer dynamic range I heard at the venue.
Now, I have my hope that this actually not so much a transducer issue than it is a fault from the amplifier. All is good and well with low level signals but things fall apart in the demanding passages.
As such, to the op, I would also recommend exploring the source and amplifier limitations besides incriminating the phones exclusively.
For the staxes sounding flat, this is a stereotype that has long lived. As mentionned above, the latest generation models have much increased apparent dymamics, much easier to drive actually, to the expense of sounding forward / bright to those used to the older warmer voiced models. Tonality, resolution, apparent dynamics and imaging are somewhat interrelated and you typically must strike a balance between the different attributes. This is where it becomes an art of designing headphones rather than mere science imo...