I also use slic3r. But I have 0.5mm nozzle and that is why the width of each hair on 3d model is 0.6mm. Some people with 0.4mm nozzle print with only one line for each 3d modeled hair and some print with two lines. Two lines might give it more bushier hair.
But it was intended to be for one line. Whatever works for you.
Can you give a picture of how hair isn't connected to the hair? I replicated your settings in my slic3r, but everything looks fine.