Is there any way we could also prevent the system from sending more than one reminder per day? Each year we seem to have a snafu with reminders where multiple reminders go out because we are editing the email subject/text and we forget to deactivate the reminder or change the send date before we edit!

Bump! Come on, scheduled reminders should be an easy feature!

Or better yet: RECURRING reminders (every week). Right now, I go in once a week, set it to "Send reminders when activated", activate, save, reopen, deactivate. 

Agreed - since we can't schedule a "you missed the deadline" email - our workaround has been to change the due date of the form - change the text of the email to point out that the form is past due and then send it.