Reincarnation - of what actually?

A significant difference between the great western belief systems (Judaism, Christianity and Islam) and the great eastern belief systems (Hinduism and Buddhism) is that the latter belief in some form of reincarnation and the former don't. Generally spoken, then - there are minor groups in western belief systems that do belief in Reincarnation. I myself have studied the possibilities of a combination of Christianity, the religion I was raised in, and Reincarnation from the moment that my eldest sister died when I was 17 years old. The event shook my beliefs fundamentally and set me to explore alternatives to traditional Christianity, including first the addition of Reincarnation and later, in my twenties, a thorough study of Buddhism.
Now, in my thirties (I turned 37 yesterday...), I consider these traditional belief systems to be an integral part of my development, but not leading in my spirituality anymore. As you can have read in my previous blog entry (http://www.vanderhaven.net/blog/20080129.html), I am now more interested in the Essence of what we are, the field of consciousness that is the observer and the observed, the source and destination of our lives.
So the notion of Reincarnation has become something that is not necessary anymore, but more a possibility. For, when we look at live in its essence and assume reincarnation exists, what would happen when we die? Do we reincarnate in some form or other and if so, what form is it?
Given that we generally don't have a clue about our former lives, it seems safe to say that we don't reincarnate as persons with the bodies, thoughts and feelings that we have now. This would not be in agreement with the ever-growing number of living creatures in the world (assuming you would not reincarnate into more than one newborn being) and, honestly, it sounds too narcissistic to me... Also, I would not feel happy to meet the guy who killed me in this life in my next life as well...
So if reincarnation is something we want to believe in, what is it that reincarnates? Feel free to come up with other suggestions, but for me the only thing that reincarnates is Spirit itself, or our common Soul, the field of consciousness that we are all part of, that forms the world around us and that is the observer of the world that it creates itself. All our thoughts, feelings and spirits are part of that common Soul as well. So what is more logical that to assume that when we die, the little part of that Soul the we call "me" becomes part of the common Soul (or rather: stays part of the common Soul, as we are all already part of It)? If reincarnation is a necessity, this would for me in essence be the way in which we reincarnate. The aspects of our lives that we call "me" become part of the universal Soul we call "we", ready to subsequently be split off again into a new being that calls itself "me" and discovers and develops itself throughout its lifetime. Thus continues the endless cycle of reincarnations of the playful Soul that always reinvents and unfolds itself.