[Brian]

Folks here read and browse the forums on an as-we're-able basis, and it does look like there's a request in the development database that covers locking individual elements.

That said, if you want to guarantee that your request is read and filed, you'll want to send it in from the Send Feedback item under the Help menu.
The number of folks requesting a change affects our planning, so doing this now still helps.

I don't see a request in the database for the ability to lock the whole file from the inspector, so emailing that would be a good idea, as well.