From what I can see, there should be no reason to remove it, other than aesthetics. Make sure there is no active rust, as that will be a problem, but the patina is just fine. Nice scales, BTW...

Speaking of, that may be a good reason not to clean it up: to do it properly, you would have to remove the scales, and may risk damaging them if you don't know what you're doing. Buffing without removing the scales would be even riskier.