Mark, Theology, and Possible Heresy

I read a commentary on the gospel of Mark today. It was a summary of the Mark's gospel as the entire book is a kind of commentary on the ethics of the New Testament. So technically I did not read a commentary. I read a thesis. I have to say to my own chagrin, that I was escstatic after reading it. It opened my eyes to two kind of related things.
The first thing that I was enlightened to was the focused ethic of Mark. This is beautifully unwrapped by the scholar Richard Hays. In a nutshell, Mark's ethic is simple to understand, and supremly difficult to put into practice. And Mark's ethic is rather cleverly conveyed. How his ethic is set forth I will not get into, but I will say that his ethic is this: The cost of following Jesus is high. In order to truly follow him we must follow in his footsteps. (Obviously!) This means that we must be willing sell all that we have and choose the path of suffering which is akin to obeying the will of God. We do not do it in order to receive a award. Obedience to God is motivation enough. Only God is able to decide what reward is in order, and he is not telling us lest our motives be less than pure. It's plain, it's simple, it's impossible with mortal man, "but with God, all things are possible".
The second thing is that this isn't necessarily the ethic of the other writers of the New Testament. Not that any fellow writers are in stark opposition to Mark's ethic, but many suggest a way of life that would allow things that Mark's harsh outlook would not. Not only this, but other writers presentation of their own worldview are distinct from one another. This reality presents several difficulties to the traditional Protestant way of doing theology. I believe that given this reality, Biblical theology needs a revamping. Protestants ( I believe that I fit fairly nicely into this category) must hold on to their assertion that the Bible is the Word of God, but must stop seeing this Word as fixed, dormant, and mechanistic. All of the ethics can be held in high esteem despite their differences. This will force Protestants to live in a constant tension. And besides, just because some things in the New Testament seem unreconcilable, doesn't mean that they are. The truth may very well be that they are reconcilable within a non-mechanistic framework. Before we feel the burden of having to make everything "make sense", maybe we should learn to appreciate what the different New Testament authors have to offer in their different perspective on the meaning of Jesus. Maybe there is more than one right way to live your life. Maybe Jesus is the key to learning how to do just that.