Question is how overkill, because I could recommend something like an ML350 G6, which is decent and has upgrade ability but is it too much for you?
Backup wise, something like Altaro to backup to a NAS.
Have a look into setting up Altaro, I don't know if it will work with FreeNas or Unraid as never used them but if you could foot the cost of server 2012/2016 I know it works there.