I'm interested in your comments on exhaust and intake lengths, thank you. Makes sense, though it seems like the realm for an expert. The R1150RT has shorter larger diameter tubes compared to the R1150GS which has longer narrower intake tubes.
I saw the UKGSER stuff and there is a thread here too on someone who sent their ECU for remapping.
My opinion is that most who use a power commander and get improvement do so mainly because the vast majority of tunes add fuel. My Wideband O2 project showed that if you add 4-8% more fuel by changing the lambda set-point you get good torque gains throughout the RPM range but especially good between 2000-3000 RPM.