So... Yeah. Couple years later I remember my password.
It's finally finished. But, as old as the topic is, I can't edit it. For anyone even remotely interested, I just sent off a PM to OD* letting him know that it's done if Bumper's still interested.
Unfortunately, it's mostly some editing and grammar fixing. As I told OD, it occurred to me too late that doing a cost-benefit and example build section in modern times is pretty well pointless; prices and availability change entirely too fast for it to be useful as reference material. The Chart discusses itself such that my commentary would be equally pointless. At any rate, the material I have up is still pretty darned accurate; I cleaned up some of the links and made sure broken ones were fixed. I guess that's the advantage of making a general guide versus a "buy this" guide. I have asked if it's possible to add an additional "Reference Material" page that the mods and/or I could edit to stay current (showing good vendors, good manufacturers, resource material and studies concerning the AR-15 and its variants, etc.).
Anyway, good to be back. It looks like this guide's picked up a few views while I've been gone, so I hope it's helped the DC community.