I think Heaven, like God and the Trinity, is not anything the human mind can really truly fathom. I think Heaven will surpass our wildest expectations and may be different for each person. We have all heard the comments of those who have died but returned to finish what they had yet to do. Their stories are similar but I can't help but feel the wee shown what they were capable of understanding and not the full glory of Heaven. I see it as one of th Mysteries of Faith.