Very few people are migrating from WHS 2011 to Windows Server 2012. Windows Server 2012 Standard or Essentials is a business platform. I'd migrate to WHS 2011. WHS 2011 will be supported for a long time and you'll save yourself a lot of headaches. Since WHS 2012 is a business platform you must be on a domain. Unless you're already using a RAID card I'd recommend using Stablebit Drivepool to pool your hard drives.