Good stuff, quite helpful to know, and not too tough to learn.

One suggestion:

When referring to NOTES, use Arabic numerals--thus 1, 3, & 5 are the notes of a major (or tonic) chord.

When referring to CHORDS, use Roman numerals--thus I, IV, & V are the chords in a typical three-chord song.

In my opinion, consistently doing this can avoid a lot of potential confusion.