I particularly enjoy how some pieces included in your video are built harmony-wise. I wonder, not ever having a chance to compose myself, which way the music is created: whether you think in harmonic functions, and then you think about the melodic line, or is it the opposite: you harmonise the tune that you've put together beforehand?
melody is always boss of the operation. actually melody and lyric together are the boss of the operation. then harmonize as needed