Maybe you’ve already made a decision on this but in general I run one helmet that tests well on the Virginia tech tests https://www.helmet.beam.vt.edu/bicycle-helmet-ratings.html

Then I use a buff/hat under the helmet on colder days. This is usually good for me down to freezing temps, generally I don’t ride much below that since I don’t have studded tires at the moment.

Wow! Thanks for putting up this super informative post and following through so many comments. I love using a waxed chain and I think it’s definitely hard for people to jump to when their bike maintenance is essentially zero. I run wet lube on one bike for wet weather riding (like >50% of the year) so I know both sides pretty well. The wax chain is so much easier to clean and maintain it’s crazy.

It’ll be hard to convert anyone that just lets their bike run into the ground before they start taking care of it, but they’re also probably on bikes that are sub $500 and aren’t looking for efficiencies or endurance performance.