I have some camo military pants that are double knee. I was a able to cut up and old closed cell foam sleeping pad and stuff in there. Works amazingly well I don't notice them at all walking around. I also put them in a pair of double knee carharts and they work well in there also.
You'll pay a lot more but ultralight poles make a huge difference. I have helinox passports they fold up really small and are super light so I take them everywhere.
I've takin my outback many places I shouldn't have or didn't think would make it.Your issue will be not having a gear thats low enough to crawl through some places.
I've gotten into these situations so many times my wife nicknamed me "I think we can make it". I was thinking about getting t-shirts made with that quote.
I had my heart set on a particular bow and went to rocky mountain specialty gear to pick it up.They have a massive selection of bows and I ended up shooting over twenty bows and was surprised at how different they shot, ended up picking a different bow. So my suggestion is to shoot as many bows...
Big fan of BA I have a twenty degree(lost ranger) that I bought almost twenty years ago and its been keeping me warm ever since. You should be fine if you sleep warm I also have a super light liner that I put in and have slept down to negative ten with no problems.