I've tentatively broken it down to these 3 concepts:
1 - formula of intervals determines the type of chord.
example:
Root + major 3rd + 5th = a major chord
Root + minor 3rd + 5th = minor chord
Root + minor 3rd + flatted 5th = diminished triad
Root + Major 3rd + 5th + Major 7th = Major 7th Chord
Root + 5th = "5 chord"
Etc
2 - root determines the key.
3 - If the root isn't the lowest note in the chord then it's an inversion.
Inversion is really just a matter of timbre preference... because the chord formula remains the same regardless?
is there another principle I'm missing that isn't subordinate to these three?
Are these three equal; or is one or more of these concepts actually subordinate to one of the other 3?
(I find that discerning hierarchy of concepts helps me to grasp material better)
thanks