What is the best full range Speaker ?

Just thinking aloud here....

If you liked the Focus, then why not try for the Legacy Whispers? Especially if you are putting them on the long wall. In spite of their eff rating, it is my understanding they work better with decent power supplies & good amps.... 200+ wpc.

Finding a pair of them for 6500 should allow you to corral a good high powered amp, like a MC602 keeping you close to your budget of $10K... but that's buying them preowned.

Vandersteen 5 and Quicksilver V4 Monos
The most important thing to have with full range performance is top to bottom coherence.
The room compensation feature in the Quatros and Five series makes this a reality.
Cheers John

Your room is not that big so you should find many practical high end choices that you might afford depending on your taste and preference.

From my discussion with Bill Dudleston, the specs of the Focus HD are 20Hz - 22kHz +/-2dB. I reviewed the Focus HD for Dagogo.com