Brad, good point on the protein. I'm working on adding it to my calculations. This will help me ensure I have good balance of calories from carbs, fat, and protein.
There's a great article called "Pack Light, Eat Right" on Thru-Hiker that covers this subject very well. At first, I was only focusing on calories per ounce to get to the lowest packed weight possible. But knew I needed to make sure I had the right types of calories as well. The article talks about the 50-35-15 trail diet, or better stated, 50% calories from carbohydrates, 35% from fat, and 15% from protein.
Here's a link to the article;