I agree with you about the grills off and I too wish the woofers were black ,
I'm not sure if an aluminum baffle frame would be an improvement but since the woofer and the baffle are the same as the 2.4 ( of which many more were built ) maybe someday the dream will come true .
A while back I had tried adding resistors in series with the coaxial speakers , they didn't sound good . Tom suggested tring a bypass capacitor on the 1uf bypass capacitors on the tweeter and the mid speakers , I found a pair of .01uf Cardas capacitors and installed them on the tweeter I can highly recommend this "upgrade" . I only did the tweeter because I think these were the last 2 capacitors for sale since Cardas stopped making their golden ratio caps a while back (bummer) .