Its all been dumbed down, comparison sites use ££ per year instead of unit cost, ofgem removed the requirement to show it a few years back and even made it hard to work out what the actual cap is.
It was removed to make.it simpler for the general public to work out what things will cost as most people budget on a monthly basis
In regards to individual device usage is there is a few things to consider.
First I think is the variance from property to property there is things like tapping supplies seemingly common in flats, there is people reporting they move from flat to their own house and suddenly for same usage pattern they have much lower meter readings.
I myself have an issue where my landlord is paying some of my electric bill as I discovered my meter goes up with everything turned off, and instead of getting electricians out to check all the flats he just came to an agreement with me to pay part of the bill. When the switch was flipped on my meter 2 lights went out in a neighbours flat. (this is my complication of moving to smart meter, dont think will ever be resolved so will be resolved when I move)
This is most likely from a borrowed neutral and should be rectified immediately as it can potentially be very dangerous, the smart meter installer should not have installed the meter if this was the case.
Smart meters are a step forward, but I feel we should be seeing watt readings on power sockets as a standard thing.
personal choice not industry thing
As for kettles they are actually efficient. Heating water in a kettle e.g. to wash up dishes is often more efficient than using a boiler to do the same thing. I found half filling my kettle is optimal as its not heating a full load but also when I drink coffee after coffee, the reboils are fast as the water doesnt fully cool down.
where you are technically correct kettles are actually a very poor way of heating water, research thermodynamics...
Also the more often you boil water the more minerals you strip from it. If you are drinking coffee by the volume you say you are then I suggest getting a one cup kettle as they are efficient.
Small ovens are more efficient than larger ones, and microwaves are more efficient than ovens.
Funny that smaller means it uses less energy to provide heat for a smaller space again understand thermodynamics...
I also found using portable heater in my room is more efficient than using my boiler, my boiler is several decades old, and on the rare occasion I need heating, the portable heater has the room up to temp within a few minutes vs needing 1-2 hours on the boiler to do the same thing, plus the boiler is heating rooms I am not using. This is going to be even more paramount given gas is rising faster than electric.
However my boiler is more efficient than using my electric immersion heater for baths.
Only heating the space you are using is a great idea in principal, but as electricity is roughly 6x more expensive than gas it's by no means cost effective, not to mention the potential increase in damp/mould in other part of the property that are not heated or aired regularly.
On a whole you make some valid points but unfortunately lots of your thinking is flawed and proven so by science..
For reference I have held a position with a major supplier for the last 25 years, I have a Electro Mechanical engineering degree and a HNC as well a HND and many many other qualifications to do with the electro chemical world. Math, Science and electricity ar my thing!