safety harness opinion(DT student)

Hi all, i am a DT design student . i am hoping to make a product that will make it easier for parents to look after their children if they have hyperactive children or just children that like to run around a lot.
i would like to know if it is possible to get your opinions on what you would be looking for in a product. I'm looking to make something like a safety harness. so if you could just answer the questions below and include your own opinion.

1. How old are your children/child?
2.Do you own a safety harness already
3. If so why and if not why?
4. If you were to look for a product that could help you watch over your children what features would you like added?
5. Do you allow your toddlers outside in the garden themselves?
6. If you went to the countryside with your children do you think it would be stressful?
7. Do you hold your child's hand when walking through town?
8. If i was to make a device that would allow you to let your child run but only a certain distance and it would be attached to a tree(for example) would you buy it?
9. If not then how would you improve the product?