The Perfect Server - Debian 8 Jessie (Apache2, BIND, Dovecot, ISPConfig 3) Virtualization

Dear All,
My use case is University + SOHO. For a research project, I have enjoyed a perfect server setup on Centos 6 for quite some time. Now I intend to move away from webhosting for my SOHO purposes. To be more future-proof with modern PHP and the like, I intend to setup a new perfect server using Debian Jessie (probably using the Nginx variant).
My plan is to use a virtual machine on a KVM host (which is physically under my control). Ideally, I would like to keep the webroot and the databases separate from the server itself to allow for best scalability and backups (relatively small server virtual disk, independent of future size of webspace). Is there more to it than mounting /var/www and /var/lib/mysql from an adequately powerful NAS via nfs?
Regards,
Michael