Wow have you seen the movie "Defending Your Life"? If not you definitely should! It's about reincarnation as well. It follows a man who lives a greedy, cowardly life, dies, and goes to this court room that every dead person must have a trial in before continuing to heaven. In order to be released into heaven, one must have lived a courageous and generous life. If too cowardly and stingy, they must reincarnate and live life all over again without knowledge of their past lives and continue this cycle until they live a life deemed courageous and worthwhile. The protagonist meets a woman in the place before heaven who dies in a fire after saving her daughters and pets. In past lives she was a whaler, an adventurer... She is definitely going to heaven and the man must prove his courage in order to go on with her. I love your story idea. It also reminds me of "Every Day" by David Levithan. Using a fantastical plot device in "regular" human societies can lead to very powerful themes and messages. Just try your best to avoid clichés, especially with the romance!