Dart technique and placement is a sewing method that is learned through experience or the study of the hobby with focus placed on that particular subject. If your looking to make your own patterns, I would personally suggest taking a look at a few sewing books that would show you the basics of dart placement. I'm sorry that I can't suggest any to you because I learned the art of sewing as a child from my mother and my knowledge is from experience.
If your looking for immediate results, you could try altering your current ALP pattern by playing with the darts and pieces. I've got basically the same head shapes for several of my patterns on file, but they are altered and require only two pieces for the head with several darts in each. You'd be surprised with the varity of shapes and facial features you could create by just playing around with the placement, size, and shape of those little darts!
-Michele