There are too many questions here, but they give you an idea of what to ask. It is certainly not an exhaustive list.
Can I encourage you to start with a thank you to parents?
Why ask questions about the rugby its self? Because they might have seen things you've seen and it's good to get confirmation of that. They may have seen things you've not seen and it's good to hear different voices. Parents might also be frustrated you are not coaching in a certain way or coaching certain elements. Their feedback gives you an idea of what you need to communicate with the parents about why you coach the way you coach.
What questions would you add?
I'd suggest you use google forms as they collate all the answers for you.
Let me know what you think. Richard@non-perfectdad.co.uk