I've owned STTNG & JM before and still have a WCS.
STTNG I don't miss, good modes and integration, but just too slow for me.
JM I absolutely miss. Hyper speed with great shots, good modes and a worthy wizard mode. Out of WCS or JM, I think I'd stick with WCS. Great all round appeal for noobs and pros alike, great theme. Concept of working towards the World Cup never gets old, either do shooting goals!