They should have almost no privacy. Tax records, holdings, school records and any other pertinent records should be made public in order to assure that only the straightest arrows get into the race to begin with. After they are in office a third party, with proper clearances, should always be recording and reviewing all communications of the elected official with the understanding that their job is to reveal any wrong doings to the proper authorities and the public.
I believe the private lives of public figures should be open to press scrutiny, because press scrutiny is apart of a public figures job. That is why they are called public figures. If someone doesn't want their private life available for public scrutiny they should not be a public figure.
I do not want anyone looking into my private life because it is PRIVATE so why would a public figure who is a normal human want any one looking into their private lives, that's what their public ones are for, as long as they act normally and like the rest of us.
The private lives of public figures should be able to have just that, a private life. I can not begin to imagine how stressful it would be to constantly have the public poking into my business. I do not care who they date, or where they went to eat for dinner, as long as they act morally right.