I only have a few, and speaking as a UK ATCO, I think we are generally lucky that we operate in an environment with excellant pilots.
But here's what bugs me:
1. Very busy frequency with lots of stepped climbs and descents, pilot continually "approaching FLxxx requesting higher/lower"...usually pilots with an A or B ending flight number
2. "Any speed at CLIPY"....especially when the frequency is busy again, if not instructed that high speed is OK, then its standard speeds. When I'm at saturation on COWLY or NW, this kind of question is not what I need.
3. "c/s, approaching FLxxx, requesting lower"
"Negative, maintain FLxxx, traffic passing 1000ft below left/right"
"Roger we have him on TCAS"
Then why the hell did you ask in the first place !!! If I gave you descent the next words out of your mouth would be "TCAS Climb"
Really what I'm saying is a bit of situational awareness, if the frequency is really going, then please no extraneous requests, if you are getting stepped climbs, and descents then don't hassle for more, we don't give out step climbs/descents for fun it's because a thousand other green blips are all going up,down.left,right etc etc.
Minor quibbles really, on the whole British pilots and those who fly in UK airspace are really switched on and great to work with. I take my hat off to you ladies and gents.
It might be interesting to hear what pilots grumbles about us are, we might be able to help dispell some myths.