I'm absolutely sure there is more to life than we know. Just 100 years ago, we weren't even aware of atoms really. We were unaware of life's building blocks. I'm sure in the next 100 years, we will find much, much more information out. That said, I simply feel like the body is a case. The mind is truly where the personality, choices, and thoughts come from. I'd like to believe the physical death of the body doesn't affect the actual life or ending of who we are either, but without a body to support an entity, how would it survive? Clearly a body is needed for one to survive, or people wouldn't have a body to begin with. We'd all be hovering [stereotypically] entities.
I'm not sure I believe in karma. When I think about it, truly, to me.. well, I think that what goes around comes around because people who do bad things open themselves to its reactions. A person who has never done drugs is not susceptible to really dying from drugs [generally; of course there are some things like medical malpractice]. Other people, like those who do do drugs, may OD. Not because karma reached them, but because by making that choice, they become open to it's backfire. For every action, there is reversely the same action.
I'm not trying to disprove how you feel or what you think. I'm just sharing what I think as well. We're all entitled to our own opinions, and I hope you go on believing what you do and let no one sway how you feel.