Make sure ATC get a good long look at the proposed changes well before they are cast in stone. Otherwise you'll end up with a dog's breakfast of a system designed by someone who has never had to work GMC anywhere, let alone Heathrow.
Take a look at Manchester. Straight taxiways with multiple letters and cuved taxiways keeping the same letter. We don't have the luxury of an expert LPO and so aircraft do take the wrong routes, frequently.
Best of luck!
(Spell checker please!)