As weird as it may seem since I love Brawl to death, I actually don't think it has the best theme out of all of them, I mean, don't get me wrong, the music's superb, but the others are surprisingly even better, the first time I heard the Smash4 theme at the start of the trailer, with all of the Nintendo franchises being showcased one after another, I felt something I hadn't felt in a long time, I don't know what it is, but there's something so...special about the Smash4 theme, when I hear it, I think of my childhood heroes all on the same place, duking it out!
It goes like this:
1.- Smash4 - Screams Nintendo heroes.
2.- Melee - Sounds competitive.
3.- Brawl - Sounds epic, fitting with SSE.
4.- Smash64 - Similar to Smash4's feeling, feels triumphant.
Again, don't me wrong, the Smash64 music at the end of the Direct gave me goosebumps like nothing else, I consider all of these songs to be almost on the same level.
EDIT: Does every thread on this forum somehow find a way to devolve into an anti-Brawl campaign?