As early of flight times as possible, think 6am or earlier.
I fly at least 100 flights every year...the last few years, including the height of COVID, 130+ easily. My passion is flying, and not the airport, so I would spend as little time in the airport as possible...usually I get in at the start of boarding, especially at my home airport(s). No checked bags even for intl flights. In and out. No way I am getting to the airport at 3am for a 530am flight. Most airports aren't even open yet that early. 5am arrival.