Well, we say goodbye to Joan and Sherlock.
I liked that this show depicted a loving relationship between working partners that never needed to go to a sexual or romantic one. A heterosexual man and a heterosexual woman are allowed to just plain like, even love one another without getting into bed or getting married! Way more unusual on TV than it ought to be.
Also it's good to see series go out when they know it's time. Too many series don't end when they should. This was a good endpoint.