I think that their private family relationships should stay private, and if they choose to stand by their parents they should not be judged for that. Most of us will never know what we would do in those circumstances.
I also think that as their titles are entirely dependent on the position of their parents (well, their father) and they did nothing to achieve them, now that AMW is no longer a prince there is no reason why they should remain princesses. If they lose (or renounce) their titles, they should be left alone by the media, unless they are implicated in scandal in their own right, in which case they should get no special protection.
As members of the wider RF, there is no reason why they shouldn't be invited to weddings, funerals etc, but as family members, not as working royals.