Nice one, Rob. That makes perfect sense to me
I always said that the goal, for anyone serious about modding the 1210, was to get it as close as possible to sounding like an SP10, by addressing all relevant areas of weakness, and which is exactly why you did what you did, and me the same!
In effect, what you then end up with is a 'neutral platform', simply hearing the sonic signature of the arm and cartridge. Have you had your SP10 serviced? For me, that would be mandatory, so that I knew that it was performing to spec, exactly the same as it did when it left the factory, and therefore capable of performing at 100% of its capability.
As you know, the SP10 is full of electronic circuitry, filled with loads of capacitors, and after nearly 50 years, a lot, if not all of them will have drifted, so if you haven't had it serviced (by someone who genuinely knows what they're doing, and has the necessary equipment, you've probably still got more to come!
Marco.