The themes in Miller's work are quite profound and also very diverse. I think that the primary theme is Miller's critique of the American Dream. The idea that success and accomplishment is driven by material conditions is an integral part of the American Dream, and one that is subjected to very challenging criticism in the protagonist and his relationship with others and himself. Your question refers to other works, and I would analyze how these other works view the issue of dreams and material success, and their impact upon their protagonists. The genre of the play medium might also allow a level of articulation and dialogue that might not be as present or as forceful with a book, and analyzing how the genre is effective in both Miller's work and the other works to which you allude could be able to reveal a further development of these themes.