I’m also worried about how much of the harmonics in the music is LOST by the amp?

+1 mostly everyone- the entire audio chain matters

@redwoodaudio
If you’re after better sound, chasing harmonic numbers will not tell you if a component sounds good in your audio chain. Also, what sounds good is subjective- some folks like the warmth of tube gear while others seek a different kind sound. You have to use your ears.

Our hearing is much more complex than current science can measure. While good measurements can lead to good sound, good measurements does not equal good sound. You have to use your ears.

Perhaps it’s semantics but we don’t usually evaluate our systems on what we lost like “harmonics”, but rather how well it performs. You’ll likely hear better sound including harmonics on a more transparent audio chain which usually means more expensive components.

If you want to improve the sound of your audio chain, you need to make sure your speaker is revealing/transparent enough to hear what the components are doing upstream. Then you can change/upgrade components to move towards the sound you find most pleasing - by using your ears.

@redwood-audio

I’m also “worried” about how much of the harmonics in the music is LOST…

seems like you were concerned with harmonics in your audio chain VS

wouldn’t it be great to see

The hypothetical “Wouldn’t it be nice if….”

The later is a rabbit hole debate with no audio benefit. “Worry” is not the same as “wishful thinking”.  I shouldn’t have wasted time on this pointless endeavor.

+1 atmasphere
Amplifier design guru Nelson Pass tinkers with harmonics sometimes adding more to his amp designs to get a pleasing sound. 
Numbers only get you so far - it’s the sound that sells. High end audio design is both science and art.