Judaism is Exclusive but not necessarily Elitist. Important distinction. When someone's trying to convert we don't look for 'the best of the best' or the cream of the crop... we just check to see if the person will follow the rules (and knows what he's getting into).
Yes, the Tree of Life... adopted as the central symbol of Hermetics (and then twisted by poor understanding)... used as the 'big secret' of many societies, including The Order of the Golden Dawn (before being partially disseminated). Also the inspiration of Tarot cards, an important tool in modern occultism.