Best midrange for active 3-way?

Well the response and impedance hump at Fs is caused by the extremely small enclosure.
As you can see that eminence closed back driver (which I also considered) has a Vas of 0,45l, which is unheard of for a 6.5" driver as I know of.

Because of the Q the response rises at Fs and this is intentional ti raise efficiency.

On the brochures they both say that it's intended as a midrange.
But I've heard that some people recommend a very large enclosure filled with polyfill for a midrange to deaden the rear wave of the driver.
Isn't it the rear wave they use to produce that SPL with closed back drivers?

Also how do you mean compensate with filters?
I was thinking of crossing it at or just above Fs, and at 3kHz, and then EQ down the humps with the DSP.

Also what did you think of a line-array of 3". Those Faitals are fullrange, but have a sensitivity of 90dB.
Then having 2 would give 93dB, 3 94,8dB and 4 would give 96dB.
And that is from 500Hz up to 20kHz.
Now I know that higher frequencies would interfere with each other, but how high could this line-array work.

A-Pillar Line Array | Page 2 | DiyMobileAudio.com Car Stereo Forum

Here is a forum where someone used 2 of the 4" faitals in a line-array. The distortion was really good.
The only problem was the measurements he took showed a large dip just where I would use them, but I think I would use 3x3" drivers instead.