Themes of improsonment within the metamorphises

So we finished the metamorphoses today, and there are a whole lot of things going on, but then end I really thought was intriguing. Gregor was happy to die happy to be let loose from his earthly responsibilities, almost as if he had been trapped within his current life by the debt his family had and the responsibility that gave him of now not only supporting himself but his entire family.  Then he's a cockroach and is unable to support them, and sees them grow and take on the responsibility themselves, freeing him from the responsibility that he felt was his. His parents and sister have a job and are on their way up, seemingly being previously hindered by Gregor's generosity. This growth at the end that he sees is really the reason he is so upbeat as he dies, he knows his life is no longer indebted to anyone, and that those around him will not be crippled by his passing.