If you're looking to avoid domain joins, I have a write-up on the connector installation,
Windows Server 2012 Essentials – Connector installation
and optionally, the icing on the case, there's this,
How to install Microsoft Forefront Client Security Antivirus on Windows Server 2012 Essentials.
My Windows Server 2012 Essentials system is handling daily backups of 12 PCs in my extended family for many months already, and running quite well as a VM under ESXi,
Microsoft Windows Server 2012 runs fine on VMware ESXi 5.1
I have numerous articles coming up that try to give a more comprehensive view of my time spent with the product, and this Superguide will be updated.
Meanwhile, here's many related articles, ready to check out today,
All 'Windows Server 2012 Essentials' articles at TinkerTry.com