The whole problem of the NIGHT/DAY thing is that these little peeps have 12 virtual hours of night, and it's no fun to play with them when they're so exhausted. Nothing you do after about 5 or 6 really helps...Even the naps only have a small temporary effect.
I love playing in the hours between 6 AM and 4 PM, because they're energized. From late afternoon and evening hours the game just isn't any fun to play. I like to play the game a bit at different times of the day, and would like the evening hours to be as much fun as the morning hours with it.