Actually according to Murray the script for GB2 was originally quite differant, but after they started filming, the studio came in and made alot of changes, mainly that the movie would now revolve around Venkman rather then the whole team, and they added a ton more special effects shots. He's always said he loves the first half of Ghostbusters more then any other movie, and theres not a whole lotta busting going on that first half so much as just the guys carrying it with their personalities and funny writing.
I agree that the least technical shots of GB is probably some of the best stuff ever shot on film, but IMO I think the effects provides the appropriate payoff that you'd expect. The gold is that they marry the nontechnical aspects with the effects perfectly.
For example, imagine the library scene without a quality ghost. The "get her" scene would feel a little empty. As it is, its perfect.
That said, the simple scenes like the guys walking up the stairs and Peter says, "tell me when we hit the 20s, I'm gonna throw up" or "where do these stairs go?"..."they go up" is easily some of the funniest scenes. But I think so much of it relies on the context that the ghost effects are legit. If they looked hokey or were simply shadows on the walls or cheap shots the film would have failed, IMO.
That said, I think GB2 did have a bad script and weak premis, but I think the banter and stuff was pretty weak and that can be laid on the actors as well as the writers for not ad libing better like they did for GB1.
For GB3 to be good I think all the actors involved need to up their games from a comedy aspect. IMO they've been away from SNL and what made them great too long.
An injection of new blood like an Aziz Ansari or someone would really help. The old guys can't do it alone, IMO. As much as I like their characters, I think they should ax Ernie, Rick, Annie and maybe even Sigourny too.
Replace them with fresh comedy talent, but not hacks. Pull proven winners who are already past SNL. Amy Poehler, etc. Basically the whole Parks and Rec cast.
) and RDJ is taking over for Winston.
