This has been discussed in the past. I think it would be nice to have the
option for the people to be updated immediately after the movie information has downloaded—whether or not the movie has be added via NMM. It's an obvious and significant convenience if movies are being added one at a time. If more than a few movies are being added, however, it's much more efficient to add and update all the movies, then select the newly added people and update them all at once.
I'm not sure how others would feel about it, but I would probably be happy with your suggestion—assuming what you mean is people would be added automatically
only if NMM is used (and it could still be optional there—just like the existing checkbox items). I would then use NMM if I wanted people information to be downloaded at the same time. If I'm adding a number of movies at the same time, I'm going to prefer to add them all first, then update them, then update all the people that were added. I would prefer to simply use NMM if I wanted this option, rather than going into
Preferences, changing the setting, then forgetting how I left it set.
Having said that, I think it would also be very cool to have a movie command to "update selected movies' people." Sometimes I find myself browsing a movie and the people associated with that movie—neither of which has been updated in some time. Updating the movie is simple enough. But if I could then invoke this command, by the time I finished studying the movie information, I would know any of the associated people records I cared to look at would also be up-to-date.
So call this a "+1+"