Hi @Derek,
No, no, no 
The problem is that your expectations are not correct. The image on the right, in your first post, is the image one should be expecting to see, i.e. a rendered image that went through a S-Curve. If it looks too dark, crank-up the exposure and be sure that your display and viewing conditions are appropriate.
Let me also paste this important quote:
Friends don’t let friends view scene-linear without an S-shaped viewing transform.
The one on the left should never be presented on display the way you did except for diagnosis purposes, e.g. antialiasing evaluation and such.