I use Sprint Name as a indication for the date of the sprint and a sprint goal.

For example (we have 1 week iteration):

2015-09 week 1 - Admin Panel Overhaul

or

2015-09 week 2 - General Acceptance Testing

The sprint goal is very important to keep focus of each team member on the most important outcome of the sprint. Thanks to this one we can focus on delivering the most business valuable stories in the first place. Moreover the Daily Scrum is driven with the information regarding sprint goal only.

Date if for the ordering purposes, and renders very nice descriptions in issue screen (available on board...) and very nice dropdown at charts screen.

Moreover we have developed a tool to build sprint reports in confluence with short summary of the sprint.

In my opinion this meaningful sprint naming convention has far more value than Sprint 1, Sprint 2 etc...

Hence the 30 character limit is... too short.
I have checked in the database and it shouldn't be a problem to extend this one.