IRIS Explorer seems really interesting! I agree with you about that "loose of control feeling". I think it is a common effect that happens every time we go to a higher level or alternative paradigm. We have to create ways to easy go trough those levels and back again.

With Flowhub you can always go inside the 'black boxes' creating your own components as reported in the "Component Editor" section of http://bergie.iki.fi/blog/flowhub-beta. It is also possible to create and remix subgraphs that is another way to abstract a complex group of components.