I think there’s a slight misconception about the purpose of the vocabulary on wanikani:
Wanikani is ultimately a service that’s supposed to teach you kanji not be an all in one introduction to japanese. The vocabulary included are reflective of that, and focus on reinforcing different readings of the kanji that you learn in each level in an order based on the “simplicity” of the kanji, so they build up in radical complexity over time. If you want to get a well rounded exposure to common vocabulary, the best way to do that is to start exposing yourself to actual japanese!
That might look like: doing graded readers (tadoku has a bunch of free good ones), listening to some beginner podcasts/videos, or even joining the Absolute Beginner Book Club and reading along with them (they just started a new manga, so it’s a great time to join! although it is “absolute beginner” in the sense of reading native level material, not an absolute beginner to japanese as a whole)