Ask HN: Need feature advice for startup

I am building a simple communication platform for small to medium companies. It is a webapp (Saas). I built a messaging system look like an e-mail and a forum for discussion. I built admin system for centralized administration. I am now building chat for real time communication. What else can I do to make it better? Actually these companies are still using a desktop e-mail client and maintain their own e-mail server for communication, which will not allow real time communication and when I was an employee of a company which was using this desktop e-mail client, I was asked to not to send too many messages because they are not able to maintain the server load. I want to change that and I also want the employees more engaged. What else can I add to make it better? Another thing is that the users are not so tech savvy. They use computer to get their work done. They do not know about blogging, twitter, social networking etc.