Nutrition percents

Unless you have a medical condition that requires it, you probably need not worry about sodium.

A ton of foods in the database don't list any potassium, even when it is present (in large part because potassium content is not a labeling requirement in the US - not sure about elsewhere).

Carbs may be worth paying attention to depending on your activity.

I personally set my protein and fat percentages at MFP so they give me a specific gram total that I shoot for daily (as a minimum); I know them so well by now that I know what the actual target is, and ignore when MFP ups my daily targets due to logged exercise. Sometimes I am over, sometimes I am under. As long as I am striving to hit my fat and protein, I am pretty content to let the remaining calories fall where they may in terms of macronutrients (I don't do a lot of endurance activity and don't really suffer, performance-wise, from having too few carbs for any stretch).

The MFP targets are just arbitrary targets. I wouldn't stress too much about trying to construct a "perfect" day, let alone regularly hitting that day.

As with all things, YMMV.

This is one way
~ reach protein target most days. Prioritize protein
~try to reach fat when you can as it is essential to lots of body process.
~eat carbs or not. If you do not reach the carb goal that is good because you have more room for fat and protein.