Also, modifying a copy of the original OEM package to remove unwanted additions to the OS shouldn't cause any issues with licensing. It's much easier to modify an existing OEM package to remove the components they have added than it is to go any other route (and cheaper, since doing so costs you nothing but time that you'll have to spend trying to build your own image as an alternative). However, you will need to work on/with and familiarize yourself with the WIM files if you haven't already, to be able to distinguish Windows components of the install package versus OEM additions to the Windows install. virtually all OEMs follow Microsoft standard practice for creating their recovery system(s) with Windows 8, so modifying it to remove the portions of OEM-specific software/drivers and such is not particularly difficult.
Regarding getting a clean image for Win 8 installs.
