Let me answer my own thread properly, since I have now had all three.
Labrador (2016–2021). Wonderful with people, ate a chappal and a TV remote, got fat the moment I stopped measuring food. Died at 11 of something the vet thought was likely cancer. Would recommend to a family with kids and no illusions about the hair.
German Shepherd (2019–now). The dog I have learned the most from and the one I have most often got wrong. He guards without being asked, which sounds great until a cousin walks in unannounced. If you do not give this breed a job it appoints itself one and you will not like the job it picks. Two hours a day, minimum, of which at least a bit has to be thinking rather than walking.
Desi (2021–now, off the street outside my shop). Has cost me almost nothing, has never been ill, understood house rules in about a week, and is the one that is actually good with strangers. If somebody asked me today, knowing what I know now, this is what I would say: get the desi. The other two are dogs you take on for a reason. The desi is just a good dog.
What I would tell my 2016 self: it was never about the breed. It was about whether I had two hours a day, and in 2016 I did not.