This is an interesting idea but would it not 'contractualize' whole
areas of equitable doctrine? Take breach of confidence - many of the
cases regarding equitable duties of confidence could at a stretch be
explained on a contractual basis but that is not what the Courts
actually decided, as I understand them - there are cases that
recognise both a contractual and an equitable duty of confidence which
are not necessarily co-extensive.

Absent statutory intervention, it would be a strong thing to say that
a contractual obligation of confidence would not bind if breach of it
was in the public interest?

Just a few tentative thoughts.
Kind regards

Ger