I think this is one of those situations where there are no "right" or "wrong" answers, different people have different priorities, different rates of assimilating knowledge, different types of projects, etc. This is why Cakewalk structured the membership program the way they did...people could update whenever they wanted, to whatever version they wanted, return to a previous version, etc.
The thinking behind this was a) people might want to delay an update if they're in the middle of a big project, b) some people might want to update when they had free time, which could be weeks or months or lots of months, and c) if there was some kind of compatibility issue, like plug-ins that worked only with older versions of Windows, SONAR could roll back to the version that was current at the time of that OS.
So I really don't see how anyone is inconvenienced by the current structure, it gives more choices (and more frequent bug fixes) than the once-a-year-big-update approach.