control panel, webmail and PMA websites can't be moved between backup servers for a very simple reason.
they're not backed up by the enhance backup servers.
PMA, i don't care about.. install a new panel server and set the platform service and PMA will be there, fully working.
there's nothing in PMA itself that requires a backup.. no data / config to care about.
there is a system in place to create a new panel server and migrate the panel. it can, and should be easier.
there should also be an easier way to backup the control panel itself. can't migrate the panel if the old server is dead and the data inaccessible. should be an easy way to install a new clean panel, even on new ip's, and import the old panel's db backup through the panel interface itself to recover a working, fully configured and populated system.
webmail.. i've stopped using a central webmail using the platform setting. wasn't entirely happy with being forced to have it on the control panel server. also liked the idea of using mail.clientsowndomains.tld, but don't like having roundcube installed and used on each webserver, so only have it on the dedicated mailserver, if people can switch between using a central webmail server and local webserver webmail then it creates problems keeping contact lists, calendar etc synced between multiple roundcube db's. what i have is still effectively a centralised webmail, but its where i choose it to be, and with the ability for the clients to use their own domain.
still can't back it up directly in enhance.. it should be. losing the roundcube db for any reason means losing all those clients contact lists, calenders etc.. that's unacceptable.