Sleeping bags is an easy one. Just buy either a Mountain Equipment or Rab one and you’ll get years of good service out of it.
Don’t start asking whether to get down or synthetic fill because it’s worse than asking which grade of Loctite to put on disc mounting bolts.
Rab do some very nice bags but all seem to be 70 / 75cm shoulder width. I have very broad shoulders and don’t think I’d fit in them. My current bag ( Snugpak Softie 12 Osprey ) is also very narrow and it’s like being in a straight jacket!. The fit with the rest of the bag is fine though. You can get “in fill” panels for the Snugpak ones but not the older models!
Off to look at Mountain Equipment ones now.
Criterion do a nice one though. 80cm wide.
https://downsleepingbag.co.uk/sleeping-bags/Criterion-Traveller-750-Sleeping-Bag-MT750.html#SID=17