I’ve just started and then deleted a response three times now, but the gist is, what about this is complex? Or, maybe a better question, how do you think it should be made simpler than it already is, without sacrificing any context?
The established system of scale degrees and modifiers (natural fourth, sharp 6th, etc) conveys a ton of information in a very concise form, not just pitch but musical function and context, and I’m legitimately curious how you’d make it better. A diatonic scale (diatonic drawn from two greek roots but essentially meaning “seven tone”) has seven pitches. We refer to them with numbers. The overall “key” of the music is the first pitch in your seven note scale, which by convention is called the root. Then it’s just second, third, fourth, fifth, sixth, and seventh. When you ascend one more scale degree and return to the root, but sounding higher because it’s now at twice the vibrational freqency, that’s called the octave, which it’s not a coincidence that the word is drawn from the Latin and Greek word for eight. But, importantly, every scale degree is a way to define that note with respect to how it relates to the “tonic” or the root, the central tone or key of a peice of music.
So, you have your scale degrees, which are simply named based on the order they fall within the scale. Then there are modifiers which describe their “quality.” I get it that the difference between “perfect” intervals which do not have major or minor tonalities and become augmented and diminished as you raise or lower them a half step, and imperfect ones which DO have major or minor tonalities is a little odd at first, but that’s based largely on their sound and is an attempt to describe what you hear - if you play a major 6th against the root, and a minor 6th against the root, you can kinda hear what I mean. The terms to describe a pitch’s quality are an attempt to describe their sounds, by sorting them into a couple broad buckets.
And then you just assemble them into chords. In conventional tertiary (third based) harmony, you basically just stack thirds on top of each other to form chords. A major third interval with a minor third interval on top of it gives you the root, major third, and perfect fifth, and is a major triad (or three-note chord). It sounds happy and uplifting. A minor third with a major third on top, meanwhile, gives you a root, minor third, and perfect fifth, and is a minor triad. It sounds dark and moody. If you were to raise the third of a minor a half step from minor to major, then it becomes a major triad, and it changes, pretty significantly, the overall sound of a chord.
Idunno, man. Maybe it helped I had some familiarity with latin from high school so I recognize all the roots, and so a “triad” being a collection of three pitches is something that just makes sense to me… but, I didn’t take my first theory class until 19 or 20, and the whole way of understanding chords as stacked thirds wasn’t presented to me until quite a ways after that, possibly after college (I don’t remember). I’m not sure where your mental block on this stuff is, but it’s really a pretty straightforward system to describe how pitches relate to the overall tonality. Maybe it’s the relational side, that referring to a third isn’t an attempt to define a pitch, but to define how far a pitch is from the root note and how it relates to that note?
I mean, that said… If you’ve got an easier way to talk about how notes relate to each other, then I’d legitimately be curious to hear it. Not to be flippant, but nothing is “a description of what’s happening” if you don’t understand the stuff behind it.