I keep things tidy all during the day, simply because I am lazy. If there was a huge mess at the end, it would stay that way.
Both kids are asleep by 7:30, between 7:30 and 8:00 I hang out the days nappies to dry for tomorrow, put on another load, fold and put away clean ones etc. And OH does the dinner dishes and tidied up any toys or discarded clothes and stuff.
So between 8-10 we can relax, it's all tidy for the morning.