You know what’s better than the “resource” URL leading to resource/index.html? Having the “resource” URL lead to plain resource.html. Then you can still have

You know what’s better than the “resource” URL leading to resource/index.html? Having the “resource” URL lead to plain resource.html. Then you can still have a directory named “resource” and any relative links in resource.html to “resource/thing” (to reach resource/thing.html) will feel natural, as “thing” is indeed in a subdirectory. (Apache supports this using “MultiviewsMatch”.)