I'm a modo convert. I was a Hex fan until Daz broke the vert order. You cannot use hex to make morphs now without having to use work arounds, as in uvmapper and or scripts that you still need poser to run. Daz does not seem to think this needs fixing. That or they will charge you for the fix as in Hex 3.

Carrara is not a great modeler, no matter what other carrara users will tell you. It is a bit better than the last version but still does not have all the tools as a modeler has as in Hex. But it's strength lies in the muti tasks that it can do, modeling is just a small part of it.

I have  and use Shade8.5 for curves and line fits. Also has great toon rendering and poser ports over to shade just as good as Vue except the shaders but has a much better render and light system.

So, the work flow your suggesting Poser/vue and a modeler. Can't help you with a modeler because modeling apps are very personal and you need to find which one works for you the way you think and not what anyone else uses or thinks. What works for me can be a night mare for you to use. You will need to try all the demos and even the free ones such as Wings3d, blender and anim8tor. 

I use Modo for most things now.