yeah, it seems to me the ideal is something with high and low density and not so much in between, a wax, and a light oil, and no middle viscosity. The hard oils give you gloss and stiffness, and the light oils give flexibility. Its surprising how much difference these kinds of things can make.
to be honest the thought occurred to use light oil, like, barely heavier than kerosene, mineral oil.
The fats naturally in skin are great but the composition of those fats depends on what you eat. That's partly why beef and chocolate make you look younger and smoother. They have stearic acid in them, which is a very rigid, glossy fat. I'm not sure what low density oils are suitable. Honestly it seems to me like something that is nearly volatile would work best, just something that adds a little flexibility to the waxes to stop them cracking off the surface of the hairs.