I know this probably goes well beyond the scope of your department but here is my wishlist that would convince me to buy windows:

1. Support for ZFS (and future open source filesystems as they appear)

2. The ability to control every service running, and good honest descriptions of what each service does. The ability to control all the servers my computer is connecting to and a transparent view of the information they are sending

3. Ability to turn off having to use Microsoft Accounts, store, etc. Leave it on by default to make your money but offer a developer version/option.