It's a good point if you don't think that you _can_ develop feature-rich software and still keep the interface nice and easy.
It's an excuse if you believe that you _can_...
I think you need to walk the line on this one. That's what we do with Apollo... We managed to include a CRM in there, and still keep the UI very simple.
Still, it's a painful transition to outgrow a tool you've become dependent on and need additional functionality to do your job.