There is a big problem with adding family members automatically that maybe you have not thought of. Oftentimes, a person may be recorded in one census with one given name and then in the next decade, maybe a nick name or something similiar-as in Lizzie, then Elizabeth, or John and then Jno or Johnnie. In cases such as this and they happen frequently, you could wind up with 2 or 3 profiles for the same person simply due to different names being used. I would advise not taking shortcuts like that. That might look quicker but in the long run could cause you to have many duplicates.