"The speakers do sound better with the BSC, it does flatten the curve and make the recording more bodied."

I think you are getting close. Let me run a couple of thoughts and questions by you. What I have found is that without a BSC circuit a speaker can sound very clean and detailed. You can easily hear fingers sliding on strings or saxophone keys reseating. The realism is very exciting. But to my ears the performance sounds light, no body or weight to the instruments. This is particularly true with a grand piano. When you add the circuit some of these details are not quite so easily heard but the performance has body and you get a sense of size for the instruments. The big grand piano has some weight. If you go too far with the circuit, the life is gone. Here are the questions that need to be thought about :

1. Are the details you hear without the BSC circuit in the right proportion with the rest of the performance? Is part of the audio spectrum dominant at the expanse of the bass and midbass?

2. Are you hearing what was recorded or an unbalanced presentation that you would not necessarily hear at a live event.

An elevated midrange can be very captivating, there are micro-details that would not be heard as clearly on a flatter speaker. Imaging seems to be enhanced. I do not believe that any detail is lost with the inclusion of a BSC circuit, I believe that the details are restored to their original volume level and this can mean that they are sometimes not as easily heard. In my opinion no signal quality is sacrificed. The biggest down side is a loss of efficiency in the mid range. The bass and midbass efficiency is not impacted.

With your drivers (Qts ~ 0.5) the influence of the circuit will be harder to get just right. You are probably getting reasonably flat bass already with a 2-4 dB loss due to baffle step. Where the circuit really shines is in low Qts drivers like the FE-206E or the Lowthers that I use. For these drivers the bass is already rolling off at 100 Hz and for the speaker to have any weight it needs to have the midrange attenuated.

"BUT I can't get out of my head that the BSC is in essence choking (attenuating) my full range's midrange, and
goes against my overall (irrational) philosophy of not letting any electronics in the way of as large a portion of the spectrum as possible. I mean, a 3 way WILL sound better than my full range, and If I played the right games with the full range it WILL perform better.

I have to seriously look deep within myself to see what do I really want from my full ranges: a) the best possible sound, or
b) the best possible sound GIVEN certain constraints (like no electronics in the middle of as large a frequency range as possible)."

I would be looking for the most accurate reproduction of a live event. I listen to acoustic jazz so the tone, size, power, and sound of the instruments is the most important factor. It would be harder to apply this philosophy to electronic music like rock or whatever they call the stuff my three kids make me listen to in the car. If your ears like the circuit, but your brain wants the straight connection, trust the ears in the end. No matter what trust your ears.

Martin