They're Dead, Jim.
>
> I've upgraded everything else (main speakers are some decent Kicker
> 3-way coax, so do get some mis-aimed highs from there).
>
Please do not use "decent" and "coax" in a single sentence: I stopped by a stereoshop a few years back and for the life of me I could not understand why would people buy that crap in the aftermarket. You could CLEARLY hear the difference even outside a dedicated room setup for demoing speakers and I am in no way an audiophile or have anything to do with audio processing and music industry as you could see from lack of posts on hifi groups, etc
Cheap separates are the way to go, just say NO to coaxials