A few quick notes:
Conspicuity: +1 for Martin's recommendation on a reflective Sam Browne. I also use a simple reflective sash. I have a mesh vest with back-and-front reflective strips, but use this mainly for city riding, day & night. Basic mantra here, though, is:
Never assume motorists will see you.
Always assume they will not. (In 'Straya, they have a tidy abbreviation for the problem: SMDSY: "Sorry, mate didn't see ya!")
Jerseys: +1 for the recommendation (was it Julian's?) on Ground Effect clothing. I have several, and they're all well-made and durable. Not cheap, but their quality makes them v good value. My preferred item is the dual-fabric, comprising an inner layer of merino & an outer layer of polyester. Only drawback to this for me is that above about 26 degrees, I need something lighter.
Rain jackets: I prefer a jacket cut for cycling. (I have some excellent hiking and X-country skiing jackets, but they are usually bulkier/heavier than I want or need for cycling.) For 10-plus years, I've had a jacket made by MEC, and it still works well. BUT, it also weighs ~650 gms.
The top-of-line Showers Pass jacket has a good rep, but my next one will be from Ground Effect, here:
https://www.groundeffect.co.nz/collections/mens-waterproof-shells/products/anti-cyclone-performance-cycling-jacket This is lighter than my current jacket by half a pound or more, and lighter than the Showers Pass as well, for a comparable price.
I also use a variety of short- and longsleeved merino base & mid- layers, depending on the season. I've found Icebreaker to be the best. Nothing beas merino's breathability and its stinkproof quality.
Socks: My choice in socks is shaped by the fact that in the past 20 years, I've had two DVT blood clots, one in each leg. So, I'm now on Xarelto for the duration, and I've reconnoitred the market in calf-length compression socks.
From this POV, I have one categorical recommendation:
The best socks I've ever worn are the over-the-calf-length merinos made by Swiftwick, in the U.S. I find these to be fabulously comfortable--nothing else even comes close. I've worn them by themselves in X-country skiing at -25 in Eastern Ontario, skating in similar temps, and underneath motorcycle boots (behind big BMW airhead cylinders) in the high deserts of the Western US, with temps in the high 30s. A decent second place are the merino/synthetic socks made by Ground Effect. These are more durable, and their footbed is quite comfortable too. BUT their calf structure is too short for me, and their elastic band at the top is far too narrow at about 2 cms, so they're nowhere near as comfortable. (Swiftwick's elastic band is 5 cms wide, and that makes all the difference.)
Swiftwick's over-the-calf merinos cost USD 35 a pair, so they're not cheap. They offer ankle-high merinos too, and these are good for cycling, if you don't need the compression offered by the calf-high version.
As for UK brands, Bridgedale is durable, but that's all. The Swiss firm, Sigvaris, offers a full merino hiking sock, as well as a light-weight merino, both in over-the-calf height. for me, they're a step behind Swiftwick.
Hope that's helpful, though I recognize that my circumstances/requirements shape my preferences.
Cheers, John