Hello.
This kinds of graphs are also well known as signal flow graphs.
There is an unified methodology to systematically build and analysis such graphs (driving-point impedance approach and Mason's gain formula).
I personally frequently use this method for analysis of some circuitries.
If you are interested in I can refer you to:
A systematic approach to the analysis of general and feedback circuits and systems using signal flow graphs and driving-point impedance
Ochoa, A., Jr.;
Circuits and Systems II: Analog and Digital Signal Processing, IEEE Transactions on
Volume: 45 , Issue: 2
Analysis of the modified MOS Wilson current mirror: a pedagogical exercise in signal flow graphs, Mason's gain rule, and driving-point impedance techniques
Spencer, R.G.;
Education, IEEE Transactions on
Volume: 44 , Issue: 4