Do you refer to "near death experiences" (1) or to the idea that we come back as angels (2)?
(1) From my own experiences of being in heaven, I know that anything perceived in this life of the hereafter is dependent on the physical body we have being what does the perceiving. That makes it at least partially incorrect. If you compare NDE's across cultures, you cannot help but be struck how the visions are so dependent on the beliefs of each culture as to what heaven is like.
(2) This is strictly a new age teaching, and is not in the Bible. We will all share when we live in heaven together. We do share our belief in Jesus across time and space as part of a cloud of witnesses. But we do not "come back". Life is for God to love us, and for us to learn the depth of that love by sharing it with others, not for us to become mini-Messiahs or angels after we die.