Better Unsubscribe is critical
Overall, I'm completely underwhelmed by this product, and I'm seriously considering requesting a refund.
There are any number of really good competitive products that one can use with opt-in list. But a very likely target market for your product is developers working with clients who are working with purchased lists to jump start their businesses. In order to minimized potential spam and CAN act problems, a simple on-click unsubscribe link needs to be an option right out of the box, without custom coding.
The password requirement for unsubscribing is ridiculous in this type of application.