Open Question: Are these chord associations correct?

Diatonic chords often can portray certain emotions and feelings. Here is my idea of the chords. I - Tonic: the ending chord of a song, also the chord that completes a verse and gives the feeling of the music being "at rest" ii - Supertonic: a traveling chord; often moves the other chords along iii - Mediant: another traveling chord; creates a sense of deep emotion and carries a lonely sound; it may also suggest a contemplative sound. It is not common in Classical music, but it indeed has a place in ballads and R&B because of its contemplative sound. This chord is more suited for those genres than any other. Usually leads us to IV or vi. IV - Subdominant: the second strongest chord (next to the dominant); this chord is ideal for basic everyday progressions, such as I, IV, V. Carries a passionate sound. V - Dominant: the strongest chord; everything always leads up to it, then resolves down to the I chord. This chord is what helps to establish the key of a piece of music. Defines the tonic. This is the end-all beat-all chord. This is the "bulk" chord. vi - Submediant: another emotional chord, but only this time unlike the iii chord, this one is the saddest chord. It is the relative minor of the I chord. A majestic feeling can be created by raising the middle note of the chord, making it a major chord. (Example in C major: F---> G----> Em----> A) In the example from a song in C major, the vi chord is changed from Am to A (major). The transition from the Em chord to the A major chord creates a majestic feeling. viiº - Leading tone: this is a piercing chord; its main purpose is to resolve to the I chord, just like the V chord does. It is merely a reflection of V. It also can move to the vi chord. There isn't very much use of it in genres outside of Classical. Is this true?