Cotherion, The shape of the axe is somewhat aesthetic, but also has to do with performance. The three notches on top are for catching stricks when using wood to drive the hatchet through another piece of wood. The angles behind the beard actually help deflect and catch the blade from an opponent.
As far as spikes go I have made them in the past, they are impressive for sure. This was designed with the fact that an accurate blunt strike is much more likely to create a silent kill, to where as a sharp edged kill is more likely to allow for sound to escape. Sorry if that is to blunt.
The steel was selected because I found it to be a good affordable middle ground for a stainless with toughness and edge retention. I wanted to pry, hammer, chop, and still skin game. I use 154CM when requested, but for the fact that there is little to no difference ATS-34 is used to make a more affordable product. Any steel and handle material combo is available. I'm working on a O1 and 5160 version at the moment.
As far as pricing goes i'm not totally set on it yet... $190-$220 i'm still working on a good quick release kydex sheath system.