Best Towers Under $4,000 / pair

VMPS RM40 jrs. $3K, although I think they've only got a single pair left.

I'm also looking for speakers upgrade and I've been listening to a lot of things lately. Dealers are really nice around here and let us take the equipment home to try.
I have a Naim NAP150x/122x, a Rega Apollo, and a Rega P3. On my opinion (and it's purely matter of taste), the PSB Synchrony One were the best, not the best in a specific field, but the best overall. They could play anything equally good, with not listening fatigue and were so coherent from top to bottom. Plus an amazing bass response.

I had Maggie’s MG1.6 that where too bright with NAIM, I had Vandersteens 2ce Sig MKII, that where beautiful in the midrange and the highs, but the bass was really slow and totally undefined.
I didn't get to listen to the PSB two but I heard great things about it.
It's always a difficult choice.

Cheers,

Given the Macs, HT use, and the fact that you like the Celestion sound, consider something dynamic, like what I use --Revel Performa F30, a true full range 3 way tower that does it all, has audiophile refinement but rocks too. --used about $1500-1800. The best speaker I ever heard with country. I haven't heard the new Revels. The Legacy Classic and Paradigm 100 are also good choices. Vandys, vienna dont rock in my opinion, nor do planars of any kind, nor really most audiophile brands, unless you just like string quartets. I wouldn't get a B&W smaller than the 802, which is pricey used. PSB might work too. Good luck, you will know what you need when you hear it.

for Rock, my favorites will always be Klipsch. If you can place them, the Klipschhorn are just sublime really, and in your price range. If you don't have the corners available the La Scala's are almost as good. These would integrate very well with your existing gear. Heck, add a McIntosh 275 amp and go all old school. I think for home theater you may find you only need a small "Boomer" sub for the LFE effects.