"Ladies and Gentlemen, MagicMusic proudly presents: "One Man's Opinion"!!!
Just kidding DisneyMagic
I find often that when Disney recycles a tune from an old show it's because either someone connected with that earlier show has moved up the ranks and has a special spot for that tune, or that they know it's got special significance for the guests. Doubt too much that the second option will bring the music of Light Magic back, but perhaps the first will.
Disneyland Resort Paris used parts of the instrumental theme music from Light Magic in their Mickey's Birthday Surprise show in the Videopolis during its tenth birthday 2002. If I remember correctly there should be something about this in an old post here on this board.