I love that Function Editor, lol.

Never found an easier way to write computer graphics programs - without writing computer graphics programs. That's what the Function Editor lets you do, create shaders with as much power as if you were writing them in code, without knowing how to code!

Considering the creative power, my opinion is that they made it  pretty easy. Not saying there's no learning curve or that it's simple - just that it's much easier than writing the code that would give you the same creative power.

You can do simple color and bump mapping without touching the Function Editor. I expect lots of folks will never try to learn functions and you can do a great deal without them. But i'm sure glad they are there for those that want to have that power. Different strokes for different brush using folks.