I had a couple of Hasselblad bodies, backs, and several lenses back in the eighties when I had a commercial photography business. I found it useful to have a set of extension tubes. I did head and shoulder portraits with a 150 and a 250. Some folks look better when photographed closer, and some further away. Even full length has a very nice look when photographed with a 150, assuming you can get back far enough. For more informal portraits, including environmental portraits, I'd used an 80 or a 50. I also did some work for a photographer who covered trade shows around the country. I rented a super wide on those occasions. Even that focal length, 38 mm, was useful for certain types of portraiture.