Depends on the artist. The still artists want better endstage rendering; lighting, texture and shader abilities, better static posing (a lot of them without a learning curve at all, or a learning bump). Along with that, content that fits their favorite figure.

In my case I'd love a full IK solver, as that would increase Poser's usefulness as an animation tool. At the moment the endstage rendering is irrelevant to me, as I use Vue as my endstage. If they got metaball generation (aka Metaform or some similar python script) included, that would change my render profile considerably. Interior stages would be done in Poser, as the metaball system would permit running water, showers, fountains, broken pipes spewing, smoke, fog, plasma effects galore. The old Metaform wasn't RealFlow by any stretch of the imagination, but it was capable of filling an effects niche that was sorely needed, and one written today, to take advantage of the multi core processors, would speed up the simulation by orders of magnitude.

I won't even get into the '5 clicks and done!' end of things, as that is so varied in wants and needs.