Oh I hadn't thought about how it would have been marketed or planned from the beginning - maybe because I came into the show when the last season was airing. "Romance" is such a wide open category - maybe that's why I thought the hero's journey (Liz) was the primary vehicle for the plot and the romance was secondary. Since all of these characters are in their late 20s, I don't think the coming of age trope fits. The show definitely incorporates a ton of tropes though.