That, my friends, is way too complicated for this teacher. And you know what, it's OKAY not to have a million different classroom jobs.
Don't worry, this doesn't mean that I do all of the jobs myself. My classroom is a community and everyone contributes.
So, how do I make it work? I have two "Helping Hands" from each class. My school has two of every grade, and we're departmentalized, so I choose two helpers from each homeroom. My helping hands do ALL of the jobs for one week and then I trade them out. I try to choose a boy and a girl for each week to keep it even.
This classroom helper arrangement works out two-fold: all of the students get to do all of the jobs AND it rotates regularly enough that each student gets to be a helper multiple times throughout the year. I have hand prints cut outs that are laminated and sorted by homeroom. The set of students who have already been a helping hand that round are binder clipped together and kept in a plastic bag.
As I get to know my students, I do conveniently pair up a super enthusiastic helper with a less-than-thrilled helper. Also, by rotating weekly, if I have someone who I know will need a little extra boost one week (and they haven't been a helper recently), I pull their hand from the bag. You know, conveniently.
Also, as a little time management tip...set an alarm in your phone for Friday afternoons when you need to change out the helpers. I have ones for a variety of weekly reminders, including my helping hands :)
What systems have you found that works for classroom jobs?