Depending on individual snake preferences, you may need to add hides. When mine were hatchlings in their big tubs I had 2 or 3 hides. As they got older some still seemed to prefer having hides, some don't care anymore.
You'll need to mist as often as required to keep your humidity where you want it. Alternatively, you can provide a humid hide for the snake.
Ball pythons hate water bowls with patterns on them. But who cares, what do they know about decorating anyways?
You can try feeding a new BP whenever you want. Some people wait a week. I always offer mine the day or day after I get them just to see how their response is. If they don't eat, they wait til the next scheduled feeding. Most of them eat the first day from what I have seen. However, I think it's personal preference. Waiting a week has no real downside, so if you choose that route you'll be fine.
EDIT: I type too slow. I could have just agreed with the post above had I seen it before I started.