Greg
Welcome sir and a very insightful first post.
Regarding amps I view them as a tool in the tool chest. My encouragement to you is to have a list of amps that will drive your Thiel’s easily with enough dynamic headroom. The sonic flavor is subjective. Having enough power is not subjective. This coming from the designer himself.
For your Accuphase choices the P-7500 will be the better performer at mid/higher volume levels and better bottom end.
With Thiel’s I never warmed up with the pairing of them with Esoteric. I had the K-01XD and although it will WOW you with its clarity and transparency it just never made the emotional connection with me and the music. It mated better with a speaker with a slightly warmer presentation.
The way to find out is switch your DAC out with a R2R ladder or a analog sounding Delta Sigma such as the Bricasti M3 and models above.
I’m not promoting a component brand. I’m promoting to test what you have with what you do not know.
You have put together a nice rig so congrats. There is no “low mid-level audiophile system”. It’s "your" system to be enjoyed by you and those you chose to share it with. Your money, your choices, your enjoyment.
The issue, and probable death to this hobby is the belief of a hierarchy that the more you spend the more you must love music.
I’m confident you will get better advise from the many knowledgable Thiel members here and hope they welcome you as you haver a seat at the table also.

