So in other words, Space/Time are the extremes for passiveness and activeness, while Breath/Blood are that for idealism and realism. Every Session needs at least a Space and a Time player, but perhaps an "ideal" Session would also require a Breath and a Blood player, while a "perfect" Session has 12 players representing the 12 Aspects. In terms of storytelling, aside from setting (Space) and narrative (Time), a plot (Breath) and characters (Blood) are also required, with all 12 perfecting all.
Something like that. Sburb (and perhaps Paradox Space as a whole) is an rpg. For an rpg to function, you’ll want both a Setting and some ability for the player(s) to take Action. For it to function well, you’ll want to strike some kind of balance between scenes based in overarching Plot and scenes based in Character Interaction (as Tex Talks has noted, the story took a rather drastic swerve toward the latter when Karkat took over as focal character from John for Hivebent). The remaining eight fill out the spectrum for what kind of story Sburb/Homestuck/Homestuck fanfiction featuring other sessions is/can be.
Coherence and Contrivance, Story Speculation and Character Interpretation, Background and Spotlight, Downfall and Accomplishment. Arguably all of these are essential to a well told story.