Not bad for a first try Pete, I have seen worse from so called Electricians, someone has already mentioned the IP issues on the upper part of the CU where the cables enter.
I'll mention a few others which are only aesthetic, ready?
You could try and keep all the cable entries to just one entry point, save a lot of messing about cutting numerous entry points
Purely my point of view get yourself some cable numbering sleeves to number the cables, ie 1s on all the cables for the first circuit 2 for circuit 2 etc they aren't expensive, looks more professional, makes it easier to identify cables if you have a problem and testing, good try though mate keep practicing.
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