Would it be possible to create food items that would cancel the fatigue effect, then? Instead-of-resting like. Could be useful, especially when you get your cleric to cast restoration... And no need to add new status icons 
Quite easy, actually. It'd be a matter of creating a potion-type item and using the "cure opcode" opcode in its effects, with the opcode for fatigue as the argument. Get
DLTCEP which is by a wide margin the most intuitive editor if you're accustomed to GUI (
IE, Windows) systems, install it per instructions, and open one of the "POTN" items (
IE, POTN09) and take a look at it in the editor to see how it works.
You could also fiddle with scripting a bit to have characters refer to being hungry on certain timetables (you'd want to use the text-over-head action, probably; I forget which that is), as well as the "normal" fatigue thing, but that take significantly more work. You could even set local variables for the characters to interact with scripting to make them "hungry" after an elapsed time since the last meal, with the timer reset by eating. The portrait icon is the thing that I'm most skeptical about, actually...
Though I still don't think very many people are going to install this mod, honestly.
"Tyranny is a quiet thing at first, a prim and proper lady pursing her lips and shaking her head disapprovingly, asking, well what were you doing (wearing that dress, walking home at that hour, expressing those inappropriate thoughts) anyway? It's subtle and insidious, disguised as reasonable precautions which become more and more oppressive over time, until our lives are defined by the things we must avoid. She's easy enough to agree with, after all, she's only trying to help -- and yet she's one of the most dangerous influences we face, because if she prevails, it puts the raping, robbing, axe-wielding madmen of the world in complete control. Eventually they'll barely need to wield a thing, all they'll have to do is leer menacingly and we fall all over ourselves trying to placate them." -godlizard