Now that you have groups working, you could add a new feature: SMS Merge. In the message, we could write #firstname or #fullname and MightyText would change each sms with the firstname or the name of the contact that it is sent to. There isn't any app that provides that over the web, only in the phone itself. You would be unique!
Lee Fakes commented
My reason for purchasing the Pro version was the group send and templates. I didn't expect that a template wouldn't have a merge function. Adding this feature will allow me achieve what I purchased the App for which is to send Service Reminders to my customers without having to sit and do each one individually.