The arm on the Rega is way better than what comes on the S. No need to upgrade unless you want to spend $15 K. Wally will supply shims of just about any angle.
IMHO the two best tables Kuzma makes are the Ref 2 and the M. My favorite Kuzma arm is the 4 Point 9. The R has to be put on an isolation platform adding to the cost. Tables with a magnetic thrust bearing are quieter.