I think this is all really great, except for one thing. As teaching tools the suggested displays (spiral, feather and "natural" [sic]) would be disastrous , all giving the appearance of a main trunk with side branches, suggesting to the layman that this is a reasonable picture of evolution when everyone involved in teaching evolution knows that this is one of the main misconceptions that we constantly have to fight.
A useful presentation must have a structure that at every node produces branches of equal thickness, with the same weight and angle.