I think that the most striking similarity would be to analyze how both Romeo and Tony react to seeing the object of their infatuation. When Romeo first sees Juliet, he describes her in a manner that captures a moment in time, and what pure beauty resembles:
He [Romeo] compares her [Juliet] beauty to the brightness of torches, a rich jewel in an Ethiop’s ear, and a snowy dove.
This is similar to how Tony describes his vision of Maria in the song, "Maria:"
The most beautiful sound I ever heard:
Maria, Maria, Maria, Maria . . .
All the beautiful sounds of the world in a single word...Maria, Maria, Maria, Maria . . .
In both descriptions, the beauty of Juliet and Maria are brought out in full detail, and to the extent that whatever injustices might exist in the world are rectified with the presence of this "other." It is here where I think that some differences might exist. When Romeo encounters Juliet, his love for her is prefaced by a melancholy over his failures with Rosaline. Juliet becomes a great "rebound" for Rosaline. Yet, for Tony, his feelings of melancholy do not arise from a failed love, but rather from a lack of direction. Tony finds himself adrift of wondering where his direction in life is to be. No longer with the Jets, working at Pop's store, and wondering if "Something's Coming," the preface to his seeing Maria is not a failure in love like Romeo, but rather a sincere questioning of identity and place in the world. For both young men, the frustration of consciousness is replaced with love inspired by stunning beauty.