My point to Ked.
It seems like the plinth weight/mass is far greater than the original, as well as likely the platter.
Is it greater than that of the SP10 platter? The reason I ask is because you made some assumptions about the SP10 based on platter weight. If you don't know the respective platter weights between the Monaco and SP10, there is no basis for reaching such a conclusion. I have no idea, I'm just asking for the data so that you can support your thesis.