You might think about bringing in a social element... just a brainstorm, but the ability to follow other people's alerts, broadcast alerts to Twitter, alert leaderboard (pseudo-trading), etc. Good luck with your project.
Thanks, social element is a great idea! I would not come up with this one...
I was thinking about fantasy trading (which you called 'pseudo-trading') and it's on the TODO list already (our streaming engine already allows to run fantasy trading over all the supported exchanges and markets). I will definitely implement it combined with the social elements sooner or later (currently working on the project as a hobby).