There was something really satisfying about this one. I found myself trying to click as fast as I could to see if I could place nodes faster then they could produce energy. There are some fun directions you could take this one. It would be interesting to see how the gameplay changes if the nodes get more expensive depending on how many have been placed. I guess I'm still in out click the energy counter mode and I want a fighting chance :D.
On a different note I really relate to what you said about scoping in software engineering vs. in games. There's so much extra complexity to even simple games they can sneak up on you.