The above presumes a Christian-normative account of Jesus - there is also a Muslim one (where he is seen as a prophet) and various others. Also, the three-pronged classification is very simplistic - many "people potentially worth emulating" have some flaws, sometimes fairly serious - anything but "I want to be like this person in every way" might suggest that someone might have a philosophy or set of ideas that is overall good apart from some rough buts, and so people might prefer to be "strongly inspired" by someone (e.g. Bill Cosby) despite some (potentially serious) flaws.

Whether one can divorce the theology of Christianity (or any faith) from their norms and outlook towards various topics is a complex question - some parts of Torah (for example) suggest that there are not-explicitly-deity-related reasons behind much of the behaviour expected of people living in a community - one could concievably identify these and build the practical parts of a life-philosophy out of these (people who want something more complete would ideally try to extrapolate new foundations this may rest on).

The above examples of why Christian practical-philosophy divorced of its theology don't work are not so simply flawed - for example, "the meek shall inherit the earth" might easily be understood to be a denunciation of power politics as the only legitimate way for societies to be run - those who value cooperation, civility, and other ways to be civilised might do better in aggregate than those who live in a society where everyone tries to maximally assert their will on everything all the time (see Freud's "Civilisation and its Discontents" for more on the notion that some forms of repression are potentially healthy for society).

I am not suggesting that people necessarily go this route, but the above criticisms are at least incomplete.