Personally, I dislike slow zombies. Sure, they may be "the classics", but who cares. I highly doubt that anything that slow and weak and stupid could pose a serious threat to human life. In the old movies, they were only a threat because the main characters were stupid, not because the zombies were dangerous. Zombies that can run and jump pose a higher risk to humans since, well, humans have to do more than crawl to get away from them. /rant
To answer your question, no. There is no mod of a mod to make the gameplay worse.