Here are some improvement suggestions for the Support System plugin:
1. Allow non-registered users to submit tickets.
2. Adding any additional features and the ability to control more of the front end interface (from the backend of the plugin).
If you're interested in considering a WP Support Ticket System (to use as a comparison) to see what your Support System plugin could include (to make it better), see: https://codecanyon.net/item/fast-wordpress-support-ticket-plugin/19878754
Kindly vote with +1 if you want these features in Support System plugin too.