I'm actually not the biggest fan of the, To the Edge music that played in Warrior of Light. Wasn't bombastic enough for me I guess. But considering how it was made, it's really hard to ever say anything negative about the piece. To which it's arguably one of the most highly replayed FFXIV tracks on Youtube. Doesn't take much to guess why.
Personally, I'm more of a Close in the Distance person. Some of the solo duty songs like from Shadowbringers are also kind of impactful for me too. Raktika and Raz-da-han other good pieces.
A canidiate for one of my least liked songs is Labyrinthos and some of the slice of life kind of music that's been around since ARR. Just bored of them, no other reason than that.