The future-proofing of my archives has turned out to have an advantage that I didn't foresee. Previously, when browsing my site statistics, the frequency/number of hits was attached to a filename like "000134.php," which is obviously very cryptic. But now, with the new system in place, I can immediately see which posts are receiving the most attention and can realize right away what the post is about.
I still need to go back through my site and change all of the internal links (those posts that link to other posts) to the new scheme. All of the old files still exist (e.g., 000134.php) so the links won't break, but as soon as I change the (X)HTML and CSS of the archive template, the old files will undoubtedly render poorly.