We know and aren't going to get a Ghostbusters 3, should it happen still, where the old cast are in the entire movie. But how large should their roles be? I'm thinkin in what amount of screen time should they appear through the film? I'm trying to think of a simliar situation in other films. All I can think of are two of the Star Trek films. Star Trek Generations the way Shatner was in the bookends of the film. Or like how Chekov and Scotty were only in the start. Or the old Spock in the new Trek film, Nimoy was in it for like 11-13 mins. So how large of a role do the old GB's get? I think its key that they may appear in situations like the Star Trek films as needed. But I keep thinking for GB3 it'll a little more screen time than the Star Trek examples. I mean they'd probably have to appear largely at the start for the establishing of bringing back the GB biz and to recruit and train the new GB's. But later on in the film do they guide/advise the new GBs throughout or do they only show up in the end and help the new guys on the films finale? I'd like to think they'd have decent roles and to the point of being relevant roles to the story. Lets face it we'll probably only enjoy the movie scenes that the old guys show up. What do you all think?

The guys should have a fairly large role in the film I feel. Because most likely by the films conclusion the torch will be passed onto the ‘new generation’. If further sequels are made it may be harder to get the originals back for more, unless in a cameo. If the film goes the way with new recruits, the old cast will probably feature alot up until the films conclusion where the new ghostbusters will past there ‘tests’ and then take on the roles as main characters in future films, or even possibly a tv series. I heard a rumour once about a live action show, but obviously nothing ever came of it.

I'd like for the original actors to be in as much of it as they can, and still be able to introduce the new players. If they're going this passing the torch route, then I would like for that theme to run all the way through the whole movie, and not just be a moment that occurs halfway in.

My hope is that both groups will be a significant part of the story. My worst fear is that after the original cast members have been introduced and these new guys become a team, the originals won't be seen again in a relevant capacity.

I'm trying to stay positive about it since it's still early, but I am concerned about what direction they'll choose to go in.