+1 on the self-hosted. A wishlist in silk accompanied by a 2-ton brick of a deal-breaker. You'd think the most solution-starved demographic for chat would be those behind a corporate firewall...
Why kill shrink-wrap you ask? Because building and then promptly forgetting about software is a thing of the past. Now we have amazing tools that allow us to build even better solutions. Things like analytics, a/b testing and the cloud are the future for software. Why continue to build in the past?