Would it be really that tricky? With the suggestions above, many could be done with simple if-statements.
#at the end of a trainer battle
pokeyen += trainer.moneyDrop
If "normal" in electives:
pokeyen += floor(trainer.moneyDrop * 0.5)
Other, obviously terrible suggestions (like joining Team Rocket) would be impossible. I couldn't think of ideas that are both good and easy to implement for all of the electives. I posted this hoping people would come up with their own, better ideas and post it here, but no one did. The problem is that if the game does not address the fact that Red will eventually learn psychic powers (if he takes the elective), but never uses them, it will be a plot hole.