I like that it's easy for customers to access their account information online, as well as being able to send in payments via snail mail or email when needed! It would also make sense if they had an app similar to Apple Pay where you could use your phone number instead of having to add another form of payment option (like PayPal).
Also, there should really be more options available with regards to customizing notifications. As mentioned above though - this does look very promising once…