I a polices of like items.

AIX policy for aix servers - where we do all local drives

and windows servers

aix_prod
aix_dev

windows_prod
windows_dev

Where my prod polices are run by a storage unit on my biggest media server
dev is run on my media servers (but the they are setup as storage groups  -
big media - little media
little media - big media)
So I can give high priority to my prod severs. and if for CC reasons I don't have time to do all servers I can disable the dev policy to make sure the prods get done,  I also have the prods start before the devs on a normal basis)

For most servers including the ones with sql I have them in the windows policy, with an exclude to just the sql dir)
Then I have policies of SQL_server name to get just the sql backups. (this is because I have to be fussy about what is backed up and WHEN it is backed up)
I have oracle and informix backups well but as these are user backups ( kicked off by cron jobs on the servers ) I just have a general informix and oracle policy with a 24/7 user schedule.

I also had to be special with clusters
One policy is cluster_system
This gets the C and system state of the physical servers
Then I have CLSTRV_servername
This has the the virtual server name and gets the resources

I know some people who have one policy for every client - to much for me, so where I can put like items together I do, and I only go to special policies when I have to be specific.