If you come across a black damped platter, it would be a very significant upgrade to your table. The platter's slightly dished surface really gets the record locked into the platter and the damping is a big plus. I don't know if there are improvements to be had with a mat on the basic acrylic platter, but I would suspect that a harder mat would be better than a felt-type mat. You could also call WT to ask- they have a couple of pretty knowledgable guys who could answer your questions.
Regards
Jim
Regards
Jim