You answered the right points; but I still feel you lump every Christian in a reductionist method here. The OT and NT both exude a wrathful God-image, but it is abundantly clear which one projects it as the chief schema (i.e., the image of God which sticks in your mind). The former clearly dictates how you see God.
There are so many different images and characteristics of God used in the Bible, and used by other theologians, I have trouble seeing how just the one variety is the only one you take to heart. Worshipers of Christ are more than able to serve without fear, but it is not being cowardly to serve out of that fear. Susan B. Anthony, Mother Teresa, MLKJ, and other Christian reformers and social movers served as Christians, following in the footsteps of Christ. I do not believe the consensus is that they served out of fear of damnation. They did not "serve god who condemned people to hell," they served God who brought salvation to all. Again- their God-schema meant something different to them through their view of Christianity.
You take issue with the various inconsistencies of the Bible, but this does not diminish the way one views their life, if done through a Christological paradigm, like these people have done. To serve in a Christ-like manner does not necessarily concern itself with how literal you take the Bible to be, or how one interprets it- which strikes at the heart of what I take to be a misunderstanding on your part on what shapes people through thier faith and religion. You only seem to embrace the negative aspect of religious doctrine, and if something positive stems from it, you only seem to dismiss it. One could say more harm than good has come from science, just as they could religion. The question which still stands, then, follows how religion is any different than the other paradigms guiding us?
I dissagree that Hobbes thought any measure of observation to the state of nature, empirical or otherwise. He and Locke both felt Man needs escape from chaos, and social contracts are the measure. How one calibrates those contracts (your "certain point") is what they disagree on. I somewhat agree with you on Man's nature, but both authors are right that by our nature, we are flawed and negative. That "Basic faith on our own decency" you call on only comes about with the formation of social contracts, with enforcement by the State. You state that "If people weren't on some level decent and empathetic, there would have been no 19th century abolitionist movement, Christian or otherwise," but if "decent and empathetic," the abolitionist movement would have happened sooner than the 19th century, no? It is because of the state in which people can function in that manner, and Christ was saying "no slave or free man" at a time when the State sponsored slavery.
These and others served precisely because they were Christian, not despite being one. If I go along and follow your line of reasoning, then at the end of the day, it doesn't matter our (dis)agreement on why states are formed, or through which foundation- Judeo-Christian or otherwise. That same fear of being persecuted by the State for infractions is no different than being punished by God for the same- they both bring about those better natures you speak about.
I would just rather see the loving, NT God image more at the forefront for you than it is, as it was for myself those aforementioned people; but when it comes to your imagery and feelings of God, to each his own. Good discussion.