Recently while going through a chronological rewatch with my girlfriend we came across "The Understudy" (S06 E24)

I remember turning to her and saying: "Oh, I love these several episodes of Frank and Kim." To my surprise the entire story arc is a single episode. I was slightly disappointed thinking there was more content regarding this situation. I feel they could have expanded on this for several episodes and/or had Kim as a recurring character that would periodically travel in and out of Franks life for better or worse. There is so much potential comedy due to the clashing of Western and Asian cultures. My (M) partner (F) is Asian so I know this well.

What are some other storylines you wish got more episodes or recurring exposure?