1. My Band 1 goes w/o charging:
No GPS, no Watch Mode - 3 days,
No GPS, Watch Mode - 2 days,
GPS (2h), no Watch Mode - 2 days,
GPS (2h), Watch Mode - 1 day.
2. I don't think our eyes are different, but the bands could be. You may have a different MS Band. My band is set on 10% backlight in the Watch Mode - the Auto Brightness doesn't work on my band in the Watch Mode. 10% backlight is not enough for outdoors. If 10% was enough, why would we ever need 100%?!
3. [I'm concerned with the time of day in the middle of a workout anyway] Some people are never concern about the time of day, but that doesn't mean that other people are not. I often choose different running routes based on the amount of time I have left before my lunch ends. Anyway, time of day is the very basic function of every watch - it must be always available.
S.
Maybe I was overly cautious about charging it for that reason, but I never even thought about watch mode draining the battery faster.
Everyone's eyes are different, but I'd disagree with the statement that there is "no way to see anything on a sunny day."
An improvement in this area would be welcome, but I'm not really sure how often I'm concerned with the time of day in the middle of a workout anyway.