I do most of my stuff on Linux, and one of the programs on there is a graphics program called GIMP. In many ways it is on the same level as Photoshop. They had the same problem in that they had users of GIMP who had used it for years and didn't want it to change, as well as users of Photoshop they wanted to attract. So they did something unique - they made the icons and menus programmable. The result is you can make GIMP look and act very much like Photoshop, making easier for longtime Photoshop users to switch over. Longtime GIMP users can stay with the menus and layout they have learned to love over the years, and the makers of GIMP can change things around to make it easier for noobs to learn.
It seems SONAR is starting down this road with the theme editor. We have already seen themes that mimic Logic and older versions of SONAR. The use of lenses can make the software a bit less intimidating by removing all of the toolbar options except for basic tasks. If the menus become adaptable, then you could literally have themes and lenses that could make SONAR appear like just about any other DAW. This makes it easier for folks to switch, and new users to learn.