The clutch on our 1999 D2 V8 is surprisingly light for the size of the clutch. My lady took it out for her first drive today, and didn't comment at all on the clutch, and she is used to driving an Astravan.
We did make sure it was lubed up properly when we had the engine out for the rebuild, there's a white HMP grease that comes with the clutch plate that goes onto the first motion shaft splines. If you have rust fretting on those splines, it won't release properly, but shouldn't affect the pedal pressure. What does affect things are the various pivot points in the cover plate where the diaphragm spring works.
Other possibilities are a swollen slave cylinder or master cylinder rubber, release fork pivot point rusty, and although it is an open joint, any stickyness there will be translated into more pedal pressure.
Last one is the correct master and slave cylinders. There are a few variants, and you need the correct piston size at both ends to get the mechanical advantage correct.
Worst of it all is that you have to strip the box out to rectify most of those faults
Peter