Nutrition
Has there ever been reasonable research done for the whole "paleo diet" hullabaloo? I know that nutritional science generally is a bit patchwork (hard to do rigorous long-time studies), but isn't the cave man diet still a bit of a fringe topic? Last time I checked this, it seems that the general opinion was that it's eating too much that's most of the problem, not eating the wrong stuff (gross simplification, of course).
That's my main problem with nutritional advice, once it goes beyond "don't eat too much": Not enough scientists. If the author of your specific diet is a doctor or dietist at all, it's mostly the work/opinion of a singular person.
I sometimes despair at the continuing growth of the self-help section(s)…
Disagree that peanut butter is to be considered "shit." It's high in calories, yes, but contains plenty of protein and good fats plus a bunch of useful micronutrients. As long as you buy a brand without added sugar + vegetable oils, it's quite healthy.
I don't completely agree with you on the fruit side, as I think most of your vitamins should come from fresh fruits, but the rest puts the basics in nicely!