Server-Centric vs. Distributed

We are looking to upgrade to an entirely OS X network in 6-12 months. Currently we are running almost all OS9 systems for servers and clients. Users use the ASIP server to transfer and store files, but they also have some files on the own hard drive. We use Retrospect Workgroup to backup all servers and all clients every night. On the client computers, I have it set to backup e-mail as well as a "Backup Folder" where they are supposed to keep their critical files. As we move to Mac OS X Server & Clients, should I move to a more Server-Centric strategy in which no files are kept on the client computers and everything is stored on the file server, mail server, etc.? Is this even possible in OS X? This would eliminate the need to backup every client computer and allow me to just worry about the servers. Is anyone doing this successfully? Thanks for your thoughts.