am glad you are the one making these videos and not me. they need to be done, this a great dead rising niche you have and im sure as time goes on you will get more and more views.
A serial killer movie where the killer is obsessed with manufacturing a generic slasher plot by murdering people but protecting his "final girl" would be an interesting premise
Zombie Genocider shouldnt be a problem. You have half of Day 3, and all of Overtime mode to get it done. You also could potentially do it in Infinite Mode if you're really desperate.