Heard a podcast where they said fresh air at night helps regulate your body temperature for sleep. They mentioned that stale air can make you feel groggy in the morning. For noise issues, I try opening the window just a crack and using a box fan for background sound. Pollen is tricky, but I check the daily count and shut it on high days. The cool breeze feels so much better than stuffy AC air. It took me a week to adjust, but now I'm hooked on that outdoor freshness.