Being inspired by Gamemaker's Toolkit's first season of its mini-series Boss Keys, which is a series that looks into the design philosophies of Zelda dungeons in terms of layout, I decided to do something similarly for the Metroid series. This idea was fueled by things like item randomizer algorithms and 100%-speedruns, because I wanted to find a way to chart out the areas of Metroid in an attempt to facilitate pathing and maybe even help Metroid fangame makers to think about design and gating in their games.
Metroid Prime was pretty easy to do, but I ran into the question of whether or not to include each room by name. It definitely helps with preliminary organization, but I eventually decided against keeping it like that for the final publication versions of the charts.
Many, many thanks to BashPrime for the assistance with testing out the logic of these charts and the individual items.