For the last 35 years on 2-4 bed houses I have installed 2 rings, Kitchen and rooms above on one ring, rest of the house on the other.
No customer has ever had any problems.
On bigger installation I will install ring to kitchen and rooms above, then 2 rings covering the rest, each ring feeding up and down.
My view is that by doing this you are spreading the load, bedrooms draw very little so why have them on their own ring, however ground floor is where the loads are.
Then there is the cable, having rings up only and rings down only uses so much more cable, not very cost effective.
As for putting in a radial for the freezer, nice in an ideal world, not practical most of the time.
When was the last time an RCD tripped and went unnoticed for more than 24 Hours, that's how long the freezer will last unopened.
The last time I heard a client had lost the freezer contents was 15 years ago and that was because the freezer failed, nothing to do with the RCD.
Based on this I think it's a waste of effort, time and clients money.
It is not a requirement of BS7671.