Even though it is pretty obvious (or at least should be) as to the process for the film I think for completeness sake the process should be included in the meta data. B & W, C-41, E6, Other (Cafenol, xpro, etc).
There is a Process tag (Xmp.AnalogExif.DevelopProcess) within the Developer section. Do you think it will be more appropriate to move it into the Film category?
I think it might be better to have it in both categories. For example ... I can set C-41 in the Developer category, as that would be the native process for a C-41 film. But if I've developed the film in whatever b & w developer I have lying around I should set the process in the Film section to b & w.
I know I can add a Process tag to whatever film I have, but I think it should be there from the beginning. Makes things a little easier.