Could you create a side-by-side comparison?

Tessellation without smoothing is more common than you might think. You usually use it with heightmaps for displacement purposes.
Smoothing may come at some point, but I don't have the time to look into it right now, so you'll have to wait, unfortunately.
Also, using tessellation with smoothing won't make your meshes use less triangles. Tessellation, by definition, creates additional triangles.

This shouldn't have anything to do with SF. It's either the texture import settings on your textures, or, most likely, your UV coordinates on the mesh that you defined in Maya

That's simply how Unity works at the moment, so there's nothing I can do about it. Another annoying thing with it, is that I can't read global variables either, they're write-only on the C# level, which is why I've locked editing them in SF.

I added a feature request for this, feel free to vote on it!
http://feedback.unity3d.com/suggestions/shader-dot-getglobalfloat-slash-shader-dot-getglobalcolor-methods

What do you mean by global textures? A Texture 2D global variable?

It appears when it's needed, unless you're using something in the code node that requires it. For instance, textures in the vertex offset input, requires #pragma glsl

Right, when you're using the code node, all bets are off :) I should add a #pragma glsl toggle under the experimental settings

How does your node tree look?

Which version of SF and which version of Unity?

Plug in Clamp01( 5 - depth ) into Alpha:
http://www.acegikmo.com/shaderforge/nodes/?search=Depth