Any question answered...

The sockets needs to be on the ring, not on an unfused spur. Normal ring mains use 30/32A fuses and 4mm² cable.
Disclaimer: I haven't been paid for this kind of advice since the 15th Edition of the IEE regulations, and I think it's pretty much prohibited for an unqualified electrician to carry out this kind of work these days even in their own home.

Thanks...

I'm only preparing the works actually, as I want to close walls / cladding now, but ultimately an electrician will come as I need a new consumer unit anyway.

L