Let's figure out first when you want to start charging. Do you just want to set a start time, or do you want to set a start and stop time? Let's just pick one for now.
If you're trying to save money on electricity, you should set it to start when the rates are cheap.
If you want to warm up the car before you leave, you should set it to be ready by the time you want to go.
Also, you might want to charge earlier in the evening instead of at midnight. That's usually when the electricity is cheapest.