A couple of thoughts, in a nutshell.
To me, it feels normal that figure mode is the place for rigging your character/object.
The character is modelled in a default pose, bones are added, then weights or influences.
So thats all normal so far
Being able to then change the pose of the figure, which will deform the mesh, allowing for fixes, would seem the common sense way to go about it.
So, as you suggested, a button to change the mode so you can test the skinning results, right there in figure mode, seems the obvious answer. (and would also be absolutely awesome).
a 'pose' button Turning button on would allow movement of figure with mesh, and allow real time fixing. Turning button off would then return figure to the original, default pose. (still paintable, but not poseable until 'pose' button is back on. ? But ,if you are finding problems with implementing this, then thats where i was coming from in the thread below.
(Deep thought started a short conversation here,
http://www.anim8or.com/smf/index.php/topic,4647.165.html which i thought had definite possibilities. Is this any help, or even plausable/possible.
It is a different approach, but same results, ie: easy testing of weights/influences.
Although it does mean creating a 'sequence preview window' (with scrub bar), available in figure mode.
A 'pose button', as you've described above, in figure mode would be just dandy. Massively cool.
A 'sequence preview' window in figure mode would also rock, but maybe not necessary if a good pose button in figure mode was possible.