I think your pricing model is not good at all. It's expensive, there is no level service, and you are using a 'credit' system instead of simply pricing in known

I think your pricing model is not good at all. It's expensive, there is no level service, and you are using a 'credit' system instead of simply pricing in known currencies. Also, how are you going to contact users on IM services? Don't the users have to add you as a friend first?