No, you are in trouble if you use the mouse only
That's the point. I don't use the mouse only. The UI of my favourite render software is highly customizable. I use a few hotkeys, i use buttons for the rest. I use what makes more sense and what is more comfortable for me.
But yeah, i am no professional. I am not under the pressure to work as fast as possible. I have the time to scratch my left ear with the right hand