Nice and neat, but with the lines bundled together and the neutrals bundled together, not 10/10.

There might be something to be said for keeping a DB out of the reach of people who are not in command of all their intellectual abilities.

As far as physical is concerned, it really depends upon whether the dwelling is visitable, accessible or for a wheelchair user.

I have to say that I can see no reason why the DB was not placed lower down in a new build, but I think that it would be unreasonable to fail it as non-compliant as it stands.

Why shouldn't it be failed as non-compliant?   Somebody didn't do it right according to building regulations.

My  partially sighted father used to try and reset MCBs with his walking stick when they tripped due to bulbs blowing. The consumer unit was about 9ft from the floor adjacent to the ceiling and the lights would be out. He usually failed and would be without lights until the home care person arrived the next morning. They would have to get a chair to stand on to reset the MCB which is  hardly a safe practice.

As far as I am concerned the building regs height regulations should be followed for a new build and rewires. Even if a couple of the MCBs are outside the recommended height range at least they can be easily accessed by most people..

I did try replacing the incandescent bulbs with CFLs but they did not last very long and usually tripped the MCB when failing! 

When working, now retired, I did get very fed up  when trying to fix problems when the consumer unit was against the ceiling above the toilet in a tiny downstairs toilet. Impossible to get the step ladders in properly,  impossible to get my big head close to see what was where and very tiring having to work at arms length. Plus the precautions needed to ensure the toilet did not get broken by a dropped tool. 

Because it probably complies with Part P, but not Part M.

I have to stand on tip-toe to reset the breakers in my DB which is above a doorway at home; my wife cannot reach them at all. They virtually never trip, but when I want to isolate a circuit, I have to use a pair of steps in order to read the labels.

I have had a butcher's under the floorboards and I am hoping that when the DB is replaced, careful re-routing of the cables will allow me to put it beside the doorway. Which is better folks, a slightly high DB, or extending all the circuits?