I can’t help with bottoms but have you considered a silk base layer as a top? The one’s rei stocks are like, ultraultralight. here’s just a basic long sleeve one. https://www.rei.com/product/802210/rei-co-op-silk-long-underwear-crew-shirt-mens
Mine all tend to be overthinking day packs and EDC stuff. An example, I am an avid backpacker but no one else in my family is. For a large family reunion they all decided they were going to climb a double black diamond hiking/climbing trail. When I drilled them about proper footwear, water, food, gear, etc, I was told I was over-reacting. So your girl here ended up doing the entire hike carrying enough extra emergency gear for four people because I was terrified that if SHTF we would all die due to lack of prep. Looking back this was a bit over dramatic of me but I did get to peacock strut about a bit when it turned into a torrential downpour and I was the only one with waterproof shoes and a rainfly on my bag…which meant I got to carry even MORE stuff on the way down. :/
I’m going to copy-paste my response from another comment here: I think undergarments and reusable pads are the best option personally but I would warn against the thinx brand specifically, there have been some questionable materials showing up in their underwear linked to cancer and fertility problems. here is a link: https://www.fastcompany.com/90450618/report-thinx-menstrual-underwear-has-toxic-chemicals-in-the-crotch#:~:text=A%20University%20of%20Notre%20Dame,chemicals%2C%20in%20Thinx%20menstrual%20underwear.&text=An%20intrepid%20reporter%20for%20Sierra,magazine%2C%20has%20uncovered%20something%20disturbing. to an article discussing the findings and statements from Thinx, and I’d encourage you to also look into it and not just take my comment as proof. Theree are a lot of smaller creators on etsy and instagram making handmade period underwear if you do decide to look for an alternative.
I think undergarments and reusable pads are the best option personally but I would warn against the thinx brand specifically, there have been some questionable materials showing up in their underwear linked to cancer and fertility problems. here is a link: https://www.fastcompany.com/90450618/report-thinx-menstrual-underwear-has-toxic-chemicals-in-the-crotch#:~:text=A%20University%20of%20Notre%20Dame,chemicals%2C%20in%20Thinx%20menstrual%20underwear.&text=An%20intrepid%20reporter%20for%20Sierra,magazine%2C%20has%20uncovered%20something%20disturbing. to an article discussing the findings and statements from Thinx, and I’d encourage you to also look into it and not just take my comment as proof. Theree are a lot of smaller creators on etsy and instagram making handmade period underwear if you do decide to look for an alternative.
As far as menstrual cups go–the vagina isn’t a sterile environment, the idea that it needs to be fully sterilized is good if you’re able but not really required. So if you can wipe your hands down and rinse them off, you’ll honestly probably be fine. Also they can be left in for twelve hours on the high side, so having to change them less frequently is good, and in an emergency you don’t have to worry about it really. That being said, they work for some and they don’t for others. I had nothing but problems with mine and ended up with urinary tract trauma because of it. For me I’d rather have reusable liners and pads and a small stock of traditional tampons to use when I know I’ll be able to get more. But i’d be interested in sharing a more thorough opinion if you open a discussion on it some time.