Seems like they were trying to make a Hellraiser at the start, then the writers decided "fuck it" at a certain point.
No more exploring the extremes of pleasure and pain and all that, Pinhead was just out for blood. I wonder if the producers stepped in at some point and told them to make get the body count higher, take the violence to slapstick like levels, bring in many ridiculous new cenobites, and so on...
That's often the case when a movie is all over the place.