Guy,
Completely fair and reasonable. No implication against ATC intended, I think you fellas do a great job considering the limitations put upon you.
Sounds like we need a cultural change, for which some open communication both ways would help, to get US to communicate when we can't achieve your clearances, and YOU to realize why.
For instance:-
Those same 777s are often the ones who "can't do" 160 kts 10 mile out!
The 777-300er at MLW, with the 154 approach speed, would have a flap 20 min speed of 169kts. To fly slower, he needs flap 30. No prob, EXCEPT we can't go beyond flap 20 without lowering the gear. Thus, to facilitate your 160 at 10 miles, he needs to go fully configured. Assuming he's down to 2000' at 10NM, dragging gear and flaps 30 to the glide-slope is worth about 1T of Kero- and we don't always arrive with that much to spare!!
Do you a deal- get a message from your management to ours that this is happening, and I'll suggest to ours they put something out saying "if you can't accept the clearance, say something every time." Be prepared for that to be a LOT of the time, however!!