Get a faderport 16 to go with the live mixer. It has more features and isn't redundant for sure. You can control 3rd partly plugs with it too. Better zoom controls, track arming on the fly....lots of stuff.
Btw, I'm liking Studio One just fine and it's something new and different for me. I'm guessing in a year or so, there will be major improvements (GUI?) that will making looking back at Sonar, less likely.