actually taking index.html out of the apache package would make installing a new homepage easier. if you still wan't to keep an index.html for RedHat Linux, it should be located on the redhat-release package
the index.html file is marked as noreplace, so if you modify it locally and then upgrade apache, you will not lose your changes.
even marked as %config(noreplace), it would unnecesarily show warnings on an rpm check, if it is changed. IMHO, index.html and powered.cgi are more relate to redhat-release than to apache taking manual out of apache for 5256, would need an scripted modification of index.html to for not showing the missing link. making a default index.html with a manual link seems to static for me, there should be a better way to put a default "it worked" homepage