>>1354307What I do to make sure the lines stay reasonably even is I work in the same zoom level the whole time I do the lines and I use the width my mouse curser as a reference.
The zoom level depends on how thin or wide I want the lines to be, so long as it is roughly the same as my mouse.
I use inkscape and in inkscape there is a way to convert strokes into fills.
I don't really suggest using it, though, as there are a lot of errors when it does this and I often find my self spending more time fixing the errors than if I had done it my self.
I'm not familiar with it but I'm sure illustrator has the same thing.
