Sketchup has the more friendly Interface user that you can find!
(we can say Moi is the SketchUp of the nurbs! so...
If you use a tablet you must have something for replace the Middle mouse whell of the Zoom in/out !
All plugins shown follow are free! (There are maybe 2 000 to 3 000 plugins! ;)
About curves you must use a special Plugins "Bezier Z" by Fredo6 for create curves like Moi Curves (even of course it's not nurbs! ;)
here only one icon function (see the tool barr ;)
About animation : natively there is automatic animation of camera beteween scenes ! And animation of Plane section!
So very efficient!
About traditionnal animation like Blender TimeLine etc... now you can with Animator by Fredo 6 again! ;)
I believe that you have better way for simple organic : make it inside MOI
For complex organic use free ones like Rocket 3F, Wings3D, MeshMixer ...exotic like TopMod, Neobarok...
or the very powerful for real organic Sculpture Sculptris : http://pixologic.com/sculptris/ then export Import inside SketchUP!
by OBJ formats!