...if you start with the cam shaft rework you will have to do the full job in my point of view - means: air filter + muffler/exhaust + ECU + cam shaft ... everything else makes no sense.
I made now all possible rework on my M3W (PB Centa / chain drive conversion / Garage 56 muffler+air filter / Oehlins / KH steering upgrade / ...) - the only missing thing is the stage 2 tuning !
Let´s wait for the solution from M3W services... as usual the will offer something good ;-)
You are missing the Roller Rocker Kit but I suspect that finding those now is near impossible.