Whether your chin is too big is for you to judge and it is clear that you think so. Chin reduction surgery can be done through either an intraoral osteootomy or a submental ostectomy depending upon what chin bone dimensions are being changed. You do not need a full centimeter of reduction, that...
Thanks for your question. Without photos and a personal examination it isn't possible to provide any medical advice. However, I would seek out a board certified plastic surgeon who is experienced in orthographic surgery. Good luck!
Chin reshaping surgery can be effective at reducing the overprotecting pointy chin especially when one is smiling. When you speak of jaw reshaping it is not clear as to exactly what you mean. A jaw that is seen as not having much definition is often referring to lack of adequate jaw angle shape....