How about, instead of adding bells and whistles to it, you make it talk to as many other services as possible? There’s a unique selling point for you. ICQ, the first universal messenger: talk to anyone on 42 different supported services.
I speak for no-one else, but I don’t want photo effects or anything like that. But I want to talk to anyone, whatever service they’re using. I have to maintain accounts on Google Hangouts, Skype, WhatsApp, Telegram, Slack, Facebook — and ICQ, AIM, Yahoo & others. Currently I use Franz (http://meetfranz.com/) and occasionally Pidgin or Adium, but if one client could talk to most of the others — not voice, not video, just text — then I’d be happy to switch.