My Series 0 regularly has more than half battery life when I put it on the charger at night after using it for 3 years daily.
If I wanted sleep tracking, I could just charge it in the morning until I'm dressed and it would probably keep up.
I don't have battery issues with my Series 0 either and never have. I do now charge it while I'm showering after my first workout of the day (1 hour workout) but I don't really need to. Just becomes part of your daily routing (you're taking it off to shower anyways, what's the difference between putting it on the dresser or putting it on the charger on the dresser?).
Seems those that still make a stink about the battery life are all folks who have never owned ones. Before the first Apple Watch even shipped there were those up in arms about battery life. Then when they got one they quickly realized it's a non-issue.