Also conversation feature (email-based) available in "Messages" tab during form submission editing also could be useful feature:

1. The email that is received by system Administrator should have in
Reply-to email address of user who's submitted the Form. In other
words if I submit a form and specify my Email address, the email that
will be received by the Admin will have Reply-To as my address so
Admin can reply right from he email client. Email field can be
identified if Validation has been set for it.

2. Ability to continue communication with User via Form Submission in
Admin. Example, user submitted a form specifying his email address,
next thing Admin got an email notification or perhaps the entire
submission in the email and now can reply from his Email Client. It's
would be quite useful if Admin can actually reply back (with
attachment) to User directly from the Admin and then user replies back
to Admin and so on. All this communication is stored as Submission
Messages of course. We'll be using POP3 and SMTP as well processing
for bounced messages. Preferably this requires a separate mail box
setup, but should work with any mailbox. Besides that there will be
multiple Statuses to help indicate Submissions that have new updates.
Also, the ability to "Save as Draft" the Reply to User, then come back
later to finish.

All this will be enabled if Admin marks something like "Enable Email
Communication" setting for the Form.