I suggest you to have a look at the following, interesting document:
-Basics of Electrochemical Impedance Spectroscopy – Application note by Gamry Instruments
Available at: https://www.gamry.com/assets/Application-Notes/basics-of-electrochemical-impedance-spectroscopy.pdf
I would just like to point out that the best equivalent circuit is not necessarily the one that fits best with the experimental curve but the one that best represents the "real" system we are studying.
That is, for each component of the equivalent circuit we must be able to provide an explanation regarding its presence.
My suggestion would be to use the ZsimpWin Software as it has multiple configurations for fitting the EIS data and accordingly, you can choose the best-fitted circuit.