Just wanted to post this in case anyone was curious.

My logic for which solar bodies to include and which to exclude has to do with these factors:

-Size
Determined by an absolute minimum radius of 125km. (125km is 1/2 of 250km and qualifies -barely- as 'size 1' on the planet scale that I've implemented.
If I can revise the scale system of this mod, this /may/ change.

-Orbital Distance
Determined by the body's semi-major axis. (The radius of the two furthest points in a body's orbit.) Anything beyond the orbit of Neptune has been excluded because:
1) Balance.
More bodies means more potential resorce deposits. An average system in Stellaris currently has less than ~10 objects in it. The sheer number of objects that I've already included is ridiculous.
2) Approximation.
Generally, it is an unstated assumption that the star systems in Stellaris are an approximation of the systems that they represent. What we see are the most important orbital bodies in a system, rather than EVERY body in a system. This was done by the developers for a variety of reasons, I'm sure, but probably just boils down to performance. In that spirit, anything in the Sol system beyond the orbit of Neptune is, well, pretty irrelevent.