I've seen this question posted many times. Hell, we've talked about it a million times here in the office. So I thought it would make sense to provide a breakdown on how big of an undertaking it would be to add Pamela as a playable killer in F13.
First, let's talk broad assumptions about Pamela as a killer. In the films, we didn't see Pamela actually kill. "We" (the audience) saw these kills from a first-person perspective, and only the victim knew it was Pamela just before they died. It wasn't until the last reel of the film that we discovered she was the killer. But think about how she killed. She was very stealthy and her kills, for the most part, were very up-close and personal. There's almost a Michael Myers approach to her killing style. Jason on the other hand is a brute killer. In the later films, he didn't care to be seen. In fact he would jump through windows and break down doors to enter a building. Very impactful, jump scare-y and athletic at times. Jason 2, 3 and 4 all ran as you're aware. He was more human. There was a stumbling/bumbling aspect to these Jasons. However, Jason 6-9 were more stoic, undead, slow and menacing.
With that said, let's talk mechanics and level layouts. We built all the maps with pacing in mind. Think about a rubber band in your mind. Put the rubber band on your right-hand pointer finger, now stretch it over to your left-hand pointer finger. Now stretch it out as far as you can, then relax it back, bringing your fingers close together. Separate your fingers, bring them back close, back and forth. That's the mindset for pacing in our game. You are one finger, Jason is the other. The mechanics we create in the game become the rubber band. How fast can the counselor run? How fast can Jason run? How fast is Jason's cooldown for his abilities? What is the distance from one building to the next? All of these are considered in the mechanics of the game. Some games create tension by limiting resources (food, water, bullets) but we do it through how we built the entire game. The level layout, the characters, their abilities, etc. It all comes back to the rubber band.
Now that you're thinking how we think, are you starting to see how difficult it would be to add Pamela as a playable character? When the level is created to make Jason's abilities shine and heighten tension as a counselor...how do you create a killer with NEW abilities? And Pamela's abilities would need to be grounded in "real life". She's a real person after all. Unhinged, but real. Nonetheless, I hope you're starting to see how much work it would be to add her. We would need a new abilities system just for her. We would need a new map, just for her. We would need to balance her abilities against the counselors abilities to make sure no one gets too much of an upper-hand. It makes my head spin to think about it.
We're not against it. We think it would be pretty cool. But it's something that would take a lot of time and money to do right. I think we could spend that doing other, more manageable DLC in the future. Manhattan/Boat, Space/Grendal, etc, etc. I hope this helps answer this question.