Turntable Upgrade Suggestions

I currently own a VPI Scoutmaster turntable with the supplied JMW 9 arm and a Clearaudio Discovery Cartridge.
I also use a Thor Audio TA-2000 preamp with phono included and Thor Audio TPA 150 (150 watt monoblocks) amplifiers.
I use a pair of Quad 988's.I am trying to improve the quality of my vinyl by upgrading turntables. My first thought was to trade for the Super Scoutmaster, but then I was advised that that table could only hold the JMW 9 arm and was made to work with that arm. What if I wanted to upgrade to A Grahman Arm or A Rega Expressimo Arm. Would any of these work on the Superscoutmaster? I was told by adding an armboard which would allow changing of arms that this owuld degrade the sound, as the SuperScoutmaster was made to work with the JMW 9 inch arm. In short, for the $5000.00 asking price of the Super Scoutmaster can I achieve better sound with a different table and arm combination. Can anybody out there any make any recommendations based on what they have personally heard?