Good tips here but also don’t let sleep tracking get in your head. You should primarily go off how you feel rather than what your watch is telling you. As long as you’re getting 7/8 hours of sleep (or more) and you feel alright you’re fine.
Otherwise see a doctor.
Yes adaptive mode is amazing. I commute into the city via walking and train a couple days a week and it is fantastic. I've removed regular transparency as well and just use adaptive when I need to hear. I feel like the people that complain that it "doesn't do anything" aren't in the environments it was made for so they don't see much of a difference, but if you're in the city or noisy environments it's a game changer.