[Storyteller.]

You know, my friend actually suggested that theory to me a couple of years ago, and it's really stuck with me. I'm not sure I believe it, exactly, but it does make a sort of sense. I haven't heard of a specific name for it, but if I do I'll let you know.
Anyway. Questioning your beliefs is fine, even good. I'm a strong believer in discovering your own path, not simply following whatever religion you were taught as a child or told to believe. Searching for answers on your own is the best way to find them, you know? As the user above me said, why do you feel the need to have a label? You can be spiritual but not religious, you can have strong beliefs but not be part of a formal religion... there are so many options.
Of course, with your talk of branches and trees and such, the obvious religion that comes to mind would be some kind of paganism - have you looked into any of the pagan paths?
On that note, keep exploring. When I first branched (no pun intended) away from Christianity, the thing I found most helpful was to look at all the other religions. Read as much as you can, talk to people of different religions, and see what appeals to you. If you want, you can pick and choose aspects of different religions to have a personal, unique faith. It's yours, after all, so it doesn't matter what anyone else thinks about it.
Finally, if you ever want to talk about this, I'm always happy to listen. I'm open-minded and I promise I won't judge you, so don't be shy.