I came here with exactly this episode in mind. I think it is representative in a few ways:

1. It involves an alien of the week.
2. The alien species is culturally similar to human societies we, as viewers, are familiar with.
3. It demonstrates what the Federation is all about, including the Prime Directive, respectfully dealing with less developed civilizations, and solving problems without violence (especially when the problems are your own fault).
4. It’s more or less self-contained. Whether this is “representative” is debatable, I guess. I think it’s a big part of Star Trek even though there’s a larger focus on season-long storylines in later series.