Some environment stuff like terrain, trees, sky with clouds etc. would be nice. I can do all this in Blender, but having it natively in Poser would be great since Poser is MUCH easier to use than Blender, at least for occasional users like me.

Especially terrains should be a piece of cace since you need only a plane, a greyscale displacement map, some realistic looking textures and a set of parameter dials to adjust all of this ...

 

And by the way: I have been using Poser since version 3 and it is getting better an better. I really love it!