I think the quick, simple answer is yes, a longer arm will affect the damping, but only in that, for a given setting the longer arm would need a slightly higher setting than it would were the original, shorter arm fitted.Will the extra length affect the damping?
And definitely don’t get your 1970s flairs out
In practice I doubt very much that I would really notice any difference in normal day to day riding. These dampers have a very wide range of settings from almost un-noticeable right up to almost locked. I can't remember what setting I have the other bike set at, but it is set very low. I expect this bike might need one or two clicks more damping at the most, if at all.
I did plan on getting some sort of a carbon heel guard made to cover the front area of the clutch cover as that is the only part that I have ever accidentally touched with my foot on a few occasions when the engine was running on the first bike. I planned to use the rear two mounting screws holding the carbon centre plate in place to secure the heel guard, but to be honest it's never really been an issue for me so I doubt I bother now.