In reply to the original question:
"Do all new Poser figures HAVE to be weight mapped":

No they don't have to. Actually weight mapping every single joint (e.g. the fingers) would be kind of overkill.
The best solution i.m.o. would be to create "hybrid" figures, which use sphere zones where sufficient, and weight mapping where sphere zones don't give you satisfactory results.
Then (if necessary) create one or two JCM morphs for the details which you still can't achieve in either traditional rigging, or weight mapping, and you should get pretty good results.

One last thing(TM): ;D
When weight mapping, pay special attention to the BULGE maps; they can work real miracles if you get the grip on how they work!

Peter