Squeak,
I do agree with your basic premise that workstations are pretty much geared towards the dance market. Those that use them mainly use them for that and is why they build them that way. Myself having owned both a Motif and Karma and still have a Triton Rack, that is definitely my take on them.

That being said though, if someone is a jazz pianist all the worksations could work for them, as they all have pretty good acoustic and electric pianos I think. However if they want to stray much away from those.....then I think they're going to have a hard time finding good "bread and butter" sounds on workstations.
jam on,
Terry