I've been considering that for quite a while now actually, but I don't know too much about the rest and need to do some research as well. Especially since you've mentioned there're lost early versions of the full game, and lost demos for the other games, it really did grab my interest. Along with Seihou Shuusou Gyoku's "Frontal Attack", I'll get into them as soon as I can. Also, thanks for sharing mate!
< Touhou Koumakyou ~ the Embodiment of Scarlet Devil (partially found early builds of shoot 'em up game; 2002)