VPI SSM Ref setup variations

I have a black platter(not the superplatter)on my SSC.Would upgrading to the classic platter make a substancial difference and in what way?

I also have the JMW9 signature arm, would moving up to the classic 3 arm be a significant upgrade.

Which upgrade would you do first, platter or tone arm?

Moonguy, is your platter the black infused acrylic or the black Delrin?

Brf,
The platter doesn't appear to be acrylic.I would assume it's the Delrin.I see the ssc's now have the classic platter.

Hiendmuse (this is necessarily verbose, please bear with me)
Firstly.
OK - a Symposium PC under each of the two narrow ends of the motor assembly is what I suspected you meant. My thought about using 3 PCs was mainly to increase stability and reduced the chance of an accident. But it could also cause micro-rocking if the base of the motor was less than very flat across the three PCs
I wonder if you tried and rejected as unnecessary or unworkable 3 PCs in a triangle under the motor base ? If I tried this I’d remove the 4 VPI squidgy feet first so I can spread the PCs out nicely.
Next.
My edenSound TerraCone feet are now in place and it looks like there’ll be a height issue which may not be the case with your BearPaws and smaller PC couplers raising the deck higher than stock feet (?) - and thus more easily accommodating the PC height under the motor.
(As an aside – I wish we could (maybe we can?) attach photos in these threads)
My TerraCones with their point-capturing brass footers lift the deck about the same height as the stock feet (as you’d expect). There is some height adjustment on the TerraCones but not much. I think the intent is to enable levelling rather than significant height variation.
PCs under the motor will lift it about 7mm higher than stock squidgies. This will have an effect on where Rim contacts platter or belts engage grooves (in my Superplatter). For instance it seems the periphery ring would rest on the Rim Drive pulley when on the platter with no LP. Looks like it would be at best a near miss when in use.
Belts – the manual pictures the two pulley belts in place below the two platter belts. I’d have to have pulley belts ABOVE the platter belts or again have contact with the ‘at rest’ peripheral ring. And I don’t know how off-spec it would be to have pulley belts high up on the motor spindles rather than at the bottom.

I think all this may mean PCs are a bit too tall to use with TerraCones ?

If so, any other suggestions to bypass the stock sguidgy feet under the motor – or am I wrong about the heights ?

Moonguy
I haven't tried alternatives to the Symposium Ultra platform. I'm very happy with it - as are a number of others discussing VPI. Idon't feel the need to try anything else and buy in to their coupling vs decoupling logic (hence why I've changed from VPI standard feet on the SSM)
I also have quite a few other Symposium products (RollerBlocks etc) and am very pleased with all.
As a second string you might try the edenSound slab which is also receiving gosh-wows from VPIers.