Frequency Response

You can't simply isolate the speakers. Are you listening to 'test tones' or music. My speaker have neither a great F Response nor linearity, but many who have heard them would say they're musical. The partnering equipment says a lot about the FR is heard.

I was also in the camp of single full range driver(no crossover) midrange is the King....until one day I realized that music is full spectrum, means you need highs and you need lows, even the super lows to have the full picture....now I am JBL 4350 guy.....so more is better. Go for the most extended and most sensitive you can get.

I am considering Tannoys
93 d/b sensitivity, frequency range of 29hz-22khz @ 6d/b
PS....After a lot of research I have never heard the term linearity until this post.

Abbys and a NSM15EXP sub hooked up in parallel to speaker taps provides me a full spectrum without a xover.

you might hear speakers' mid-range being described as "ruler flat" across a certain frequency spectrum. That basically means there are no peaks or valleys in the response that affect the lows, mids or highs. This is my understanding of what linearity is.
Be careful of specs that say "+/-6dB" in the frequency response. my Quad 22L2s are spec'd down to 30Hz, but on a +/-6dB axis. In my room, auditioned with test CDs and music, I doubt they'd rate much below 38-40Hz on a +/-3dB axis. They certainly don't produce as much bass as my cheaper monitor audio Bx5s, but I still love the Quads' soundstage and mid-range sound.
There are other things to consider besides frequency response, like sensitivity, it's important because it affects which amp you pick. Those Tannoys might be easier to drive than most.