I'm (usually) a night owl too but lately, for some unknown reason, I've been waking up at 6-7 every morning feeling fine, and I agree. An hour or two of time before the day is an hour or two when you're still fresh, so I find it easier to use this time to work on a personal project, play music, or some other productive/enriching thing. An extra hour or two at the end of the day is usually just eaten up by pointless things (e.g., entertainment after I'm already 'fully entertained').