SBS 2008 to Server 2012 R2 Standard

Hi all,

I'm preparing to do a migration of SBS 2008 (DNS, DHCP, Exchange, AD, Fileserver and a few apps that I know the ins and outs of) to Server 2012 R2.  I've got the 2012 R2 host set up and updated, and currently am installing 4 VM's to manage the roles that I need.  My current outline looks like this:

Client-DC:  AD, DNS, DHCP
Client-FS: fileserver, minor apps
Client-EX:  Exchange server (and related)
Client-APP:  bigger apps, SQL

I've looked around at other people's migration questions and blogs, and have determined the following procedure (criticism and links to other useful / disaster preventative notes would be appreciated!):

1)      Install AD Services & DNS.
a.      Forest prep the SBS 2008 to new schema
b.      Join existing domain and promote to DC, no role migration at this point. (happy to commit and just roll this over at this point, ideas       welcome).
c.      Install and Configure DNS, DHCP etc.
d.  Migrate exchange 2007 to Exchange 2013 via instruction set here:  http://blogs.technet.com/b/meamcs/archive/2013/07/25/part-1-step-by-step-exchange-2007-to-2013-migration.aspx
2)      Install print services, configure & deploy via GPO. Remove old print services form SBS
3)      Use RoboCopy to replicate user files between SBS and 2012, switch users to use this as the filestore.
4)      Uninstall Exchange from SBS (if not done already)
5)      Move AD roles (must complete within 21 days).

Let me know what you think, and if you have any useful in depth details for me to review before I get started any further - post 'em!  I love to read before I start.