Hi Mark,
We have two people on staff including myself. That does seem to be alot but we have it split between Windows(7 - 12) and Mac(1-6), I handle the windows side and just supervise the Mac side of the network. Since this is so big, we have everything in the windows portion running active directory and the mac side has its own LDAP service.
I try and keep everything managed by group policy so we can keep down any managment hiccups and most pieces of software just install the second you log into the network. That helps