On the 3009 is it the interchangable headshell version? If so, try a different, better braced, headshell. I truly dislike the stock "swiss cheese" headshell on the II imp, rings like a bell.
Are the rubber grommets in place in the bedplate? If you are careful you should be able to remove them without damage (so you may replace them if you wish), On SOME turntables SOME users prefer the sound of knife edge SMEs with the without the bedplate grommets and secured with larger screws.
Are the grommets between main arm tube and counterweight stub in good shape? I have seen a number of older SMEs with saggy counterweights due to deteoration of the grommets. Replacements are available.
Have you cleaned (DeOxit) all the electical contacts?
How are the pivots? The knife edges nice and clean and well seated? The horizontal ball bearings have no notchyness at any point across the disc surface? Anit-skating string runs smoothly?
How is the external cable? I try to avoid the "cable wars" that spring up around the "sound" of cable. (Everybody ends up flaming - nobody gets convinced) However, the stock SME cable is getting up there in age and the original cable not of stunning quality to start.
It may just be a differance in taste. JaS points out the SME can sound somewhat soft, I'd call it "mellow". Have not spent much time listening to the 1200 arm - perhaps it is "zingier" and you like it. (I wonder if the bass issues JaS has heard with the SME is the result of the stock headshell)
I would expect the 440MLa to be a good match to the SME, but can't say I have heard them together. Have you played with preamp loading to tame the 440MLas tendency for a hot treble?
There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.
Hamlet Act 1