The one thing that ultimately molds Christ into something unappealing to nonbelievers are Christians themselves. Stereotypically Christians are extremely hypocritical, judgmental, and holier-than-thou. The simplicity of who Christ is tends to be lost in translation because many so called Christians fail go grasp it themselves. Humanity is an absolute mess and can in no way live a perfect life up to the Biblical standards in the Old Testament.
The whole point of the Old Testament is to prove that living a perfect life is absolutely impossible. Our inability to live up to Gods standards is punishable by death. God then in turn creates a compassionate and awe-inspiring hand of grace. He creates Himself as a sacrifice to prove His love to pay the penalty of our sinful nature. He could have made us robots to do what He says, or just came down and laid the smack down... but He gave us a choice. That choice entails a relationship to invest our live in thanksgiving for paving a way in love from death. All we have to do is accept the fact that He did sacrifice Himself on the cross for us.