Your idea is vastly more sophisticated, and you’re getting some great feedback from people, but just FYI I just posted A Day off Work, where you spend the day bumming around the city. One possible outcome is to end up a zombie going around attacking the same places you might also visit as a regular person.
I just went with a single variable, energy, which decreases every time you go somewhere and increases whenever you eat somebody. Eating somebody successfully depends on whether you have the element of surprise, as well as who in particular you go after, and there’s also an element of random chance. You don’t make it too long regardless, so a fair amount of the text is devoted to describing, in a darkly comical fashion, different ways that you as the zombie meet your end.
@EndMaster makes a good point about embracing your zombie-ness rather than trying to stay human. If it’s in any way inevitable then all the choices you make before full infection will seem pointless.
Your whole concept actually reminds me of the book The Road, where the starving survivors have all chosen whether to become cannibals or not. It would be interesting to explore how peoples’ high and mighty rhetoric dissolves the moment their personal safety is at stake.