Design? Design what exactly? An electrical system? LMAO!!! Yeah, there's a real lot of "design" going into ensuring there's a series of sockets available near to work benches.
And of course there's a hell of a lot of "design" in ensuring that light is cast where it's needed eh? Don't talk such utter rubbish please, there is no design in this, it's called common sense. Do I need a socket where I'm going to be welding? Yes - Install one!
Do I need good lighting where I'm going to be welding? Yes - Install one!
Do I need a socket/light where I'm going to be sanding, drilling, cutting, routing? Yes - Install one.
Sorry, but not only do you keep proving that you lack the knowledge to do this job safely, you also demonstrate that you do not have the right attitude. I'm not a professional trying to protect my trade (see my sig), but I can see someone like the previous owner of my parents house - which was a BIY nightmare when they bought it with dangerous electrics and dodgy pluming all over.
Yes, each circuit must be
designed - not just thrown in. While it may well seem like most installations are just thrown in with no design, in part that's because the spark will have done designs before (and covered 'standard' arrangements during training) so that he knows that certain arrangements will work without doing an individual design on them. Once outside those 'standard' arrangements, then the sparky will need to do a little more work.
When I had an EICR done in my flat, the quite experienced sparky told me he'd need to double check something - and went off home and checked his books to verify whether the submain fuse needed changing given the length of the cable (it did).
IMO, your proposal won't work - either satisfactorily or at all. Fire up a big (or even medium) welder on that and there's a good chance of just blowing the fuse - at the house end which will plunge you into darkness, which means your installation couldn't really be considered to meet the general requirements that the installation be suitable and safe for it's intended use. We used to have a large box of 13A fuses collected over the years - they went down quite quickly with the welder before dad put a 16A socket on the ring (protected by a C16 MCB, and it's roughly in the middle of the ring so unlikely to cause overloading of either cable).
But you also need to consider loop impedance. Don't know what that is ? Then you aren't competent to design an installation. it will be significant using the materials you've described, and it's possible you might not meet the disconnect times required. Do you have the tools, and know how to use them, to measure actual impedances once it's installed ?
So do you know what the supply impedances are (both Zs and Ze) ? Have you worked out the loop impedances of your proposed circuits (both R1+R2 and R1+RN) ? When you add them up, do you achieve values that are low enough to guarantee timely operation of protective devices ?
When you can honestly answer YES to every single one of these questions, then, and only then, could you be considered to have designed the installation to be safe. You won't be able to - you've demonstrated by your posts that you don't know and don't care.