Okay I had no idea how to describe this phenomenon, so I’m just gonna do it here because the title is an absolute spaghetti mess.
So I noticed (sometimes in the description, sometimes by myself), that kanji with certain radicals have the same on’yomi reading every single time.
For example, I found that all kanji with the radical squid have the reading of けん. https://www.wanikani.com/radicals/squid
According to some descriptions, all kanji with the radical lifeguard have the reading of こう. https://www.wanikani.com/radicals/lifeguard
Obviously my only examples are from the WaniKani set of kanji, and I sincerely hope that all other kanji that have this fall in the same boat, but do you all know any other examples? Getting a list of this would make it very easy to learn a large set of readings.