It was recently shown that coplanar waveguides (CPW) leak power in the form of a surface wave above some critical frequency, and that this leakage can cause undesirable crosstalk and package effects. Further studies reveal several interesting behavioral features, including unexpected sharp minima and dimensional dependences. The authors describe these new features, and systemize them to indicate when the leakage effects are strong and when not, when interesting unexpected sharp and deep minima (cancellation effects) occur and how they depend on the structural parameters, and how the leakage behavior varies significantly when the CPW width changes from finite to infinite.<>