Obeying the Highway Code
Mind you that seems to have gone out of fashion for all road users, cyclists, pedestrians and motorists
Bloating the Highway Code with a load of evidence-free (and sometimes contrary to evidence) shoot in 1999 brought it into disrepute IMO. The cycling-specific section ballooned from 6 rules (3 of which were already a bit dodgy) in the 1970s edition to 24 rules now (and I'm not even going to count how many are bull), for example. The full code doubled from 150 rules to 307, from a 52-page glovebox/pannier booklet to a full 152-page rectangular-spine paperback to leave on the bookcase. It was a massive backwards step.
I'd love a reasonably lightweight commute bike with a chaincase.
Cases are pretty difficult with derailleurs but Raleigh still make a chain guard with a cutout for a front derailleur, part ACD215, which is pretty widely stocked by local bike shops in transport cycling areas and orderable elsewhere. Similar ones are available from SKS and Axa but aren't as easy to find in the UK. Most of them require you to remove the bottom bracket cartridge and fit the guard's support bracket behind around it, so it's easiest done at new BB time anyway.
Long socks with the trousers tucked in, as worn by the guy pushing off. Every club cyclist wore those during the winter -
Now banned by UCI rules, aren't they?
"Socks used in competition must not extend above
the middle of the leg. Ankle socks are also allowed unlike long socks" And loads of club racers follow UCI rules even when they're not obliged to.