Cauliflower Cheese, for me, is an absolute MUST for a Sunday Roast. I can say with absolute confidence that the Rowbarge in Henley and the Bull in Wargrave do the best Cauliflower Cheese EVER with, perhaps, the exception of my sister-in-law who adds leeks to hers.
A Yorkshire Pudding with my roast is a standard expectation, regardless of meat choice, but I think most pubs now just serve them with all roasts as the norm. At any rate, it's been a while since I've had to pay extra for one.
Isn't it about time that Cauliflower Cheese was a standard roast item too!?