Not sure if this will be any use to you. Generally the Perlmonks are the best people for Perl advice, but you seem to be after a design decision rather than a technical question, and I don't think you will find that answer online!
Regarding option 3, is there any reason you cannot nfsmount the files from the backup server? That saves you having to maintain direct web access to the backup system, which is surely a good thing. Information on NFS is in any good Linux manual, which of course as a sysadmin you will have right to hand ;-)