In identifying your sub-genre you can better target your readers as well as the types of publishers that look for that type of tale. Not only that, it’ll help to make useful comparisons to other, well-known books in that sub-genre which may, with luck, help you sell more!
The crucible is one of the simplest and most effective plotting tools. At its core is the relationship between the protagonist and the antagonist. The conflict they share spawns plot. It illustrates wonderfully the interwoven relationship enjoyed between character and plot.