lfm
Now as my Sonar membership expired in feb, I have looked to see what major stuff was saved up for one year anniversary and probably the largest crowd of users are to open their wallets again.
To my disappointment - nothing was saved up - not a single surprise feature?
If Cakewalk had done that, some would complain that the marketing people at Cakewalk forced engineering to hold back on an important new feature just to make people upgrade, that really sucks, I'm switching to Reaper, etc. No matter what Cakewalk does, there are people who will complain about it.
The crux of your post is about what matters
to you. I guess VCA faders matter to you because you might need them someday, but they don't matter to me. Nor does being able to put buses or folders within folders. You didn't mention Drum Replacer as a major 2015 feature so I guess it didn't matter to you, but I've salvaged many a track with it - and its audio-to-MIDI triggering capabilities, combined with Melodyne's audio-to-MIDI, are incredibly useful...but only if you use MIDI. The Paint tool, which is quite cool, also matters only if you use MIDI. Enhanced Clip support has been a big deal for me, as have the optimizations - SONAR has never been faster - and VocalSync. But, if you do only instrumental work and never need to do ADR, then VocalSync wouldn't matter to you.
In March we had Tempo Detection so you can have tempo follow freely-played parts or parts without a click automatically - that's huge (Studio One is the
only other DAW that has it, although it's a more cumbersome implementation). However if all you do is four-on-the-floor EDM, then it wouldn't matter to you. The new EQ and Multiband linear phase, channel independent, mid-side-friendly processors are exceptionally good processors by any standards. But if you don't care about mid-side processing, are content not being able to process the left and right channels independently, and are happy with the phase issues of analog emulations, then they wouldn't matter to you.
Personally I think the idea of holding back stuff just to lure people into renewing goes against what the Membership model is all about, which is to allow Cakewalk to release new stuff when it's ready. I felt Newburyport was a lackluster update, but after seeing what happened in March and April, it's understandable - Tempo Detection and the new processors are complex features, and Cakewalk waited until they were ready.
Because I work with a huge variety of projects, from narration to video scores, all the features mentioned above are useful to me. If they're not useful to you...well, then they're not...which to most users, is probably as irrelevant as their being useful to me.

All that really matters, and frankly all that
should matter, is whether the features are useful to
them.