To summarize: you place Jesus squarely within the framework of the first-century Pharisaic movement.
A notable segment of Christian scholars has taken a similar approach over the past few decades. At first, they worked primarily with rabbinic materials from later centuries, a very useful exercise though they sometimes fell into the trap of anachronism. If memory serves, Pauline scholars led the charge. Later, other scholars applied similar methods to Jesus studies. I think the approach has yielded good fruits, provided we keep in mind that first-century Pharisees cannot be simply equated with later rabbis.
I find myself in sympathy with the approach, not least because it redresses an old tendency among some Christians to insist on radical discontinuity between first century Judaism and Jesus. To my mind, in terms of Christian theology, the Incarnation requires Christians to assume the full humanity of Jesus. To be human is to be immersed in one's birth culture. Whatever else we may choose to say about Jesus, he was a first century Jew.
That being said, Jesus took the available resources of his culture (Torah, methods, etc.) and used them creatively. You point out that this has been the approach of the rabbis over the centuries, and I agree. From time to time,though, Jesus appears to have been criticized for not citing sources (i.e. other teachers, etc.). Christian commentators frequently note this and conclude Jesus claimed a kind of autonomous authority that scandalized Pharisees. I would be interested in your take on the matter.
I agree strongly that one of the major dividing points between Jesus and most others had to do with "neighbor." The division carried over into the early Christian movement. In my opinion, it drove the late first century divide between Judaism and emerging Christianity. Modern Christianity continues the debate within itself--just who can be considered a neighbor and treated accordingly.
In my opinion, the question of neighbor is the great issue of our time. How we view and treat one another is the filter through which all theology must be strained.