Nigel, your post describes several deficiencies in the ATC service provided; from lack of awareness and poor training to kamikaze flow control.....but of most relevance....the demise of what was once a healthy familiarisation flight scheme.
I urge you and fellow pilots to add comments to your voyage report.....if your chief pilot considers the accumulated reports to be significant...forward them to the CAA. You are customers and you really must lodge a complaint or comment to ATC whenever the service provision has been less than ideal...and I suggest that anything over 70% R/T loading is a justifiable safety concern [studies done in 80's].
Help us to help you, and remember that not all controllers have an interest in aviation, some just do it for the money.