I recently had a visit to Nats and sat on the Gatwick Director position.. The atco I talked to was quite surprised that converting us at a late stage to an Rnav caused us a lot of button pushing and rebriefing.
This was reinforced when another atco plugged herself in and asked an aircraft if they would do an SRA for her currency. You could hear the big think bubble coming from the aircraft!
30W I totally agree with your point 7. I sometimes wonder if the two entities are actually talking to each other.