Use a specific form for viewing and editing records based on a value of the record

IMHO it�s worth the hassle to use form rules.

Keep in mind that you do not want to think about the fields to show and hide and require interms of the Roles first.

Rather, think about each field or more ideally section as to under which circumstances of Roles should see that section. The Rules will be clearer and not conflict if you just work on one section at a time and make a rule for that.