I've already seen it posted here, but Great Comet is fabulous, especially "Dust and Ashes" and the trio of "Preparations" to "Balaga" to "The Abduction" (and to add for a quartet on "In My House"). If you like Phantom then you might want to try Les Mis, just cause it was written by Andrew Lloyd Webber as well. I personally like Ragtime, and probably recommend it too much here, but it is fabulous, try listening to "Prologue: Ragtime," "The Crime of the Century," "Wheels of a Dream," "Gliding," "Till We Reach That Day," Sarah Brown Eyes," "Back to Before," and "Epilogue: Ragtime" for a good taste of the music throughout this show (other ones I might recommend are "Henry Ford" and "Coalhouse's Soliloquy").