Early Years aka 93-95 I believe are the higher end compression years.
Far as Cams, I will repeat that last time we tried to change duration, in a OBD II LH car the computer refused to run it properly on a driveable scale. I am hoping OBD I would not care as much. We tried a 3.8 cam which had just minor extra lift and duration. PCM would not drive it at any reasonable pace.
Also, 2nd Gens got some of the extra power from tighter tolerances, hence they are interference motors. Softer Springs would not increase or decrease seeing that as one valve is opening another is closing so they equal each other out to be honest. If anything with higher RPMS you want higher seat pressure from a spring to prevent valve float. Also the PCM prgormaing, and re-designed-everything pretty much is the cause of power.
Far as lift, cam and rocker arm ratio is what controls the measurement. Once again you are playing with internals that can "kiss" so watch out. The fact the first gen 3.5 can snap a belt and not automatically grenade is a great thing.