I've hesitated about posting join this thread, but I thought that my personal experience here might help the exchange of views. I served in a number of RN unit and staff appointments thought the 80s and 90s into the 00s, mostly at what became better known as SO1, SO2 and SO3 levels.
I have to observe that during that time, there was a clear and regrettable tendency across all three services (and the Civil Service) to inflate the ranks required to hold down a post. In my direct experience, I left an Engineering Authority post in the early 90s as a Lt Cdr (SO2). Seven years later, that post was held by a full Captain. The 'grade inflation' outstripped my modest abilities to move up the ladder, and potential jobs were accelerating away from me.
This was a true 'tri-service' issue. The honest truth was that the officer 'class' of all three services were doing nothing more than looking after themselves by inventing ever more spurious reasons to award themselves higher pay via promotion. And it led to devaluation of ranks and distortion of effort right down there ladders. Again, in my direct experience, I encountered SO3s doing tasks that not only could have been carried out by SNCOs, but should have been. The SNCOs would have made a better fist of them. Meanwhile the SO3s were rightly getting fed up with the way that they were being under-employed.
This effect was noted a few years ago in evidence to parliament, and I remember some interesting graphs appearing showing how the numbers of OF-5 and OF-6 posts had just exploded, particularly during the 90s, across all three services and the CS equivalents.
My take is that the UK Armed Forces need a serious 'reset' on what they expect their officers to do at the various ranks. It would not only give the taxpayer better value for money, but also far more rewarding and enjoyable jobs for the junior officers - and that would lead to better senior officers.
Hope this helps
Engines