I'm glad the "Guilty pleasure" classification exists, because that hits it on the head for me.
While the premise is TOTALLY contrived, it's a fun show and, I think, very hip for its time. It bridges the gap between really corny television and television that featured hip people. It also is a fascinating period piece. The fact that the show is so dated (e.g. "I like all my executives to be married executives") is part of its charm. It's a bit of a time capsule showing you how how upwardly mobile single people in the city perceived themselves in the late 1960s.
Bonus points for Stuart Margolin, Angel on The Rockford Files, being a recurring character.