Without spending too long looking at this (At work), I’d question the logic of protecting cables rated at 7.5A with an MCB rated at 10A.

You could be thinking that you have all these separate loads and wiring them back to a star point, but if you have a single point failure (most common) and you generate a fault current larger than the rating of the individual circuit wiring is rated to, but less than the mcb, then you’re not protecting that circuit.

Back of my mind there is head room built into all the specifications, but on paper your choice of power cable doesn’t quite match.

The mcb is specified to tolerate the states current, and will trip some way above this (google fussing factor, or something similar) your power cable should be rated accordingly.

Btw, personal thoughts: you’ll get frustrated with 4m reels of cable!, better to get a big reel of a neutral colour and cable markers, or at least larger reels of the main black/red if that’s your colour of choice.