When the stock valve springs go away so does the noise for the most part assuming the piston fit is proper. The SE255 is not a lazy ramp cam by any means but many of the aftermarket cams out there including some of Andrews native and grinds for other companies have fairly stout rams as well. Lifter preload, rocker side clearance, pin to lifter clearance and such things are just nuances, not the root cause nor the ultimate fix. Oil is another red herring but when a 20-50 with a high VI is used that is my choice then get to the root cause. Sure put some 60w in there and it gets quieter but that is a band aide.
I too own a CVO and it is noisy. No time to mess with it. First bike I have ever owned that will get ESP and I will play the dealer game.
Saw the Indians yesterday was afraid to test ride one for fear it would put my CVO to shame in the quality dept. The motor was quiet.