The term easy is relative. There is a learning curve with any complex modeling software. Once you get past the basics with any 3d CAD or modeling software it is relatively easy to change any aspect of a 3d model. You can change a human head to a cat head if you wanted to. Rhino is definitely easier than Fusion 360 for those types of changes though I have not used it. I have used Fusion360.

I would recommend trying out some free or low cost programs to get your feet wet and see what you like or don't like.

Blender 3d is a polygonal modeling software (free).
Moi3d or Plasticity are 3d CAD (relatively low cost).
Zbrush is industry standard for digital sculpting but on the same level of cost as Rhino.

Good luck. Modeling in 3d is a total blast and a ton of fun.