I noticed there are some profiles in Vuescan for some B&W negative films. Is there a way I could make my own profiles for various negative and developer combinations, or is this not worthwhile?
In my opinion, not worthwhile. Though I think the program lets you make a film.icc file (color space) but I think this is for color films. The B&W list provided in the drop downs is hard coded by Ed and while the setting does adjust contrast I think they are ballparks at best.
It would be more worthwhile just using Vuescan for its variable exposure function and batch mode capabilities and apply a curve in your editing program afterward. That's what I do. He's also put in a "low/high curve" function in recently which would basically do the same thing.