Earlier quoted context omitted.
Now the hard part: Which fields are allowed? Which aren't?
It's not so hard but does require some debate and research. Only the sensitive info needs to be contained. For [say] a webshop you have at least the name, address info, email and phone number. Perhaps payment info or coupon codes could be included. Gradually make it more sophisticated. It's just an example. The point is for stuff used often enough to find its way into html and improve. The time date picker was a fun…
Coming up with a standard form is of course the hard part, but the basics you suggest are probably in there. There is of course all the bit about falsehoods programmers believe about names, addresses, emails, and the rest:
https://ctemm.me/falsehoods/>
https://hn.algolia.com/?q=falsehoods%20programmers%20believe...>