Majestic! This should be submitted to Nintendo.
This is hands-down, THE best remix of the castle theme for Super Mario World. It definitely stands out as one of the best songs ever composed by Koji Kondo, but you have managed to perfect it for new generations.
Congratulations on your mixing talents. You have a good ear. This belongs right up there with Nintendo's own remix of this song played in Super Smash Bros. Brawl. In fact, i think it's better than that short one they did. Yours should be used for a future Mario game. It's too good a song for Nintendo to let go of.