Any mission that gives you more than 20 candy canes over 30 minutes is GOOD option. Refreshing missions for 20 rubies will give you Rare and better missions.
Before you go to sleep you should start best (most minimum possible candies) possible 4-8 hour mission
I don't think you have enough time for 3rd girl (being half way to 5000 canes), but 2nd should be fine