What about the vitamin & mineral content? Having carbs/fat/protein/calories seems to be more focused on people avoiding getting too much of "bad" stuff, as opposed to ensuring they do get proper nutrition in terms of "good" stuff. However, the interface would seem to get pretty cluttered if it was a more complete nutritional profile.
That said, general guidelines can still be given. It's important to remember that, in general, the amount of calories consumed matters the most. Other information is important too, though.