http://wiki.polycount.com/wiki/Normal_Map_Modeling#Edge_Thickness Quick tip: Look at how Thick the edge are on this example. :) Just a small helper for when you start modelling the highpoly :)
I'm afraid, that some edges are to sharp for nice bake. For example here (red): You need also more segments for rounded elements, because some problems are visible (green)If you want define better materials during modelling you can add softer bevels for plastic and sharper for metals. It will look more natural.
Good start! If im allowed to give you one piece of advice its this: create a complete Blockout first! Where every piece fits into each other, not just a bunch of cubes or something.. a nice Blockout, that pretty much resembles the finished lowpoly model, of course not as polished etc. it will help you immensely! because if…