A537 cat and fiddle is my local "track" lol does have average speed cameras on now but from Macclesfield to the the pub they don't work but from the pub to Buxton they do (I'm up there atleast once a week on my bike)
A4212 from Bala North Wales, cracking road, can be quite high speed at parts. Definitely a really early morning road so you can have a good run.
A494 North Wales. Again a cracking road, really good surface. Again early morning so you can have a good run.
There's a road in Derbyshire near Buxton called "The ditch" just off the a5270. Quite a tight road with dry stone walls both sides. 9 times out of 10 there's practically no on on it, some nice crests that you could easily take air from and a couple of nice straights that you could see three figure speedo readings on lol
That's all I can think of for now