Hi, This is my first post, I think. I've perused many threads and deeply appreciate the valuable, collaborative trove of information you have created. My situation: I recently lucked into what I think is a stock JBL 4675C pair at a modest price. 4638TH cabs with two 2035HPL woofers each, 2446H on 2360 horns (no labels), stands, N4638 networks, fine condition, except one woofer had been swapped for an aftermarket driver in 2000 (as chalked on the outside of the cone), and a local speaker technician/sound guy who is helping me has identified a defunct 2035HPL in the other cabinet. We have not checked yet for original diaphragms but will - it seems likely. Even given the flaws, the large-scale sound is the first to command the 8000 cubic foot space of my artist's studio, with which I've struggled for years - the space makes my Klipsch CF-3s sound small. The "wall of sound" effect can keep me going on my elliptical. My studio is basically the size of two double garages stacked: 20' x 22' with several open doorways and a cathedral ceiling that is 16' to the peak, of acoustic metal panels (millions of holes). My "listening position" is generally about 16' away, along the opposite wall from the 4675s, where I work on large murals. I know this is close for these long-throw horns. Sometimes I can wheel whole sections around to face the sound better and will be around 14 feet away. Music only, mostly. My goal is the best SQ I can achieve, before the cost makes it more logical to look for a better, newer system for the space. I'm guessing that upward limit is around 4-5K max. My questions for any esteemed cognosenti who may be reading: which of the following replacements/upgrades seem promising for improved SQ? I'm looking for frequency extension, accuracy, coherence, easy-flowing musicality - and whatever the opposite of "glare" or "hard" is. Music: alt rock, folk, jazz, classical, blues, R&B. I have an Ashly ftx-2001 series iii mosfet power amplifier for the lows and decent tube amps for the rest.

1. I think the 2035HPLs were value-engineered down from the original 4675's 2226 drivers, which have larger (4")voice coils. Would four good 2226s bring a leap in SQ? Or something more modern?
2. Are active crossovers virtually a no-brainer here for best SQ? I don't have one but can acquire and learn.
3. I understand Radian aluminum diaphragms can improve the slightly "hard" sound I hear from the CDs, yes?
4. I can't get berylium or the TAD 4002, but I can obtain the newer Celestion Axi2050 drivers. Anyone tried them on the 2360 horns? I've read about the downsides of diffraction slots and the upside of K-402 horns. Financially the K-402s are perhaps a bridge too far.

Any advice or suggestions you can offer will be deeply appreciated! Thank you for reading.