If any reflex clamp or weight system is going to be implemented, it’s also worth noting that a proper VPI platter should allow the groove surface of a record to make intimate contact with the platter surface.
This is accomplished by machining a proper “relief” for the record label at the inner platter area adjacent to the spindle as well as at the outer platter perimeter for a record’s potential “edge guard”.
A felt mat would be beneficial in cases where the platter surface is incorrect.