User Notes enhancement -- glaring loophole in audit trail

Our company has long used the User Notes (on Customer records, Cases, and other places) to log unstructured information -- which I believe is the purpose of the User Notes.

The problem is that users can go back and edit their notes (even when their Notes Tab permission is limited to "Create"). They can change the content of the note and, more alarmingly, the date/time.

We use several tracking features in NetSuite which create permanent, unchangeable System Notes (e.g. Tasks, changing the contents of fields, etc). The accountability problem is that all of the unstructured information which ends up in User Notes is subject to potential abuse. For example, an employee can easily create a new User Note and backdate it to meet their purposes and rewrite history. There is no logging, no System Notes, etc to create a true permanent record of when the User Notes were really entered and what the contents really were.