Final Fantasy 7 Rebirth is full of references and easter eggs to the original 1997 game, and everything that has filled out the compilation of Final Fantasy 7 since. These are some of the best ones you may have missed on your first playthrough.
Final Fantasy 7's Materia system allows you to make any party member a spellcaster, and that's still true in Final Fantasy 7 Rebirth. From Comet to Healing Materia, these are the best Magic Materia in the game.