My clients do submit quite a few tickets. They mainly use email to manage all the issues. But one way to get them more involved is if they logged into the portal and saw a list of all their tickets, there were some enhancements that would entice them to do so:
When agents hover over a ticket, there is a hover window that shows the content of that ticket. When I tried this logged in as an end-user, I did not get this effect. I think end-users will like this too and not have to click into the ticket to view some of the details.
It would be nice if end-users had 3 to 5 views that they can customize on their own.