Would it be possible to select the desktop configuration from the installer, or in the welcome pop-up after installation?
That would appear to square the circle (that the developer wants to introduce new stuff but the users want to stick to old stuff) by making the option to switch to the new more up front - I can understand that it must be rather galling to see new stuff hidden away.
It would also support some nice large pictures of what the various options look like 
Similar facilities have been/are provided elsewhere for “browser ballots” and the like, so this is not even an original suggestion …