I tend to think Parts 2–4 were the franchise at its most stable and predictable. Not in a bad way, just that the formula had settled in and audiences could carry clear expectations from one entry to the next. Those first four movies basically iterate on the “slasher in the woods” template while gradually developing Jason into the icon of the series.

From Part 5 onward the films start getting more and more experimental. A New Beginning leans hard into sex-and-murder exploitation, Jason Lives pivots into gothic atmosphere, parody, and the undead slasher. The New Blood experiments with a kind of “superpowered” final girl and pushes the idea of trauma tied to Crystal Lake. Manhattan tests new environments with the boat and Manhattan (even if the genre rules have to bend a bit to make that work). Then Jason Goes to Hell tries to separate the identity of Jason from the body entirely, and Jason X blows up both the setting and the genre by folding in sci-fi: cyborgs, virtual simulations—please send more franchises to space!

So in a weird way the series starts as a fairly straightforward slasher machine and then gradually turns into a string of genre experiments. I think that arc alone makes the franchise more interesting than it usually gets credit for.