1.
That sounds ok to me.
Are all the tubs at the same temps/ humidity?
2.
It could be yes. Ideally getting them all from the same collection would be best.
3.
I probably wouldn't bother - ball pythons aren't really that bad.
4.
Only when I smelled like food. You can also spray them with water if they hang on. If they are hatchlings then bites are more of a shock than anything else.
5.
I'd keep the settings you have already - 97f isn't going to do them any physical harm.