I doubt you would hate the CS, I would expect the handling and performance to be an improvement, just depends on your priorities?
I would recommend the DCC with 19" Brescia wheels too.
The seats are nice to have and look the part. I am not sure they would be such a great improvement over the standard seats on track.
I have proper fixed back Recaros and factory fitted 6 point harnesses in a CS from another German manufacturer, they really make a difference to how the car drives and make the Golf CS seats seem luxurious!