Well with all you want I'm not sure if you'll end with with one extra application only. Here are some remarks on the possibilities: Bryce, don't even get into it. It cannot import any poser stuff directly, you'll need to go through D/S and that can be on huge nightmare going from Poser to D/S to Bryce. Also modeling in Bryce is very far from perfect. Vue 5 or Infinite. Great for direct Poser import, but Infinite and Vue 5 are very bug ridden (seems to get worse with every update), are very very slow with larger scenes and you cannot model with it. TrueSpace is cool, but no direct Poser import at all. Also creating natural landscapes in TrueSpace is quite a challenge. Lightwave, modeling great, Poser import one huge challenge. The Vue/Lightwave combination may be a good solution, but you will go from Pose to Vue to Lightwave which just doesn't sound brilliant at all. There is a one stop solution, but I've got no experience with it a t all and that is Cararra 4 Pro. It seems to be able to do it all in one package. The feature list is very impressive, it can model, import poser stuff, create landscapes, trees & skies and has some excellent rendering features. I would really try this one first to see if it's what you need. I've noticed someone using Cararra 4 Pro & Vue 5 Infinite, but I don't really see the need of Vue when one has Carrara Pro already.

Artwork and 3DToons items, create the perfect place for you toon and other figures!

http://www.renderosity.com/mod/bcs/index.php?vendor=23722

Due to the childish TOS changes, I'm not allowed to link to my other products outside of Rendo anymore :(

Food for thought.....
https://www.youtube.com/watch?v=pYZw0dfLmLk