Thanks for your pointers.
I've been all over this volume-dependent equalization issue and while I've yet to find definitive information, I've found quite a few 7th-gen Accord owners and a couple installers who don't see a need to "clean sweep" the signal before sending it to an amp.
Still, when I look at what it costs to have an iPod interface and fairly simple LOC installed (such as the Audio Control LCi2), I'm starting to lean toward going with an aftermarket head unit. I don't really care all that much for XM. Most of the channels I listen to are highly compressed, presumably to make room for more popular offerings.
I could also live without a CD player, if push came to shove, and just load up my iPhone.
Speakers are a big dilemma. Part of me is temped to go with a simple Alpine setup (Type R fronts and backs, MRP-F300 amp, no sub, USA Spec iPod adapter, Dynamatted doors and rear deck) and call it a day, knowing that this system should sound a lot better than the factory set up.
Another part of me is willing to spend 45 percent more to add an LC2i to the mix and upgrade the fronts to Focal Polyglass, the amp to a JL XD700/5 and swap the new rears for a 10" sub.
Okay, now that I just wrote that out, it's starting to sound kind of crazy ($2200 vs $1,500).