Her interaction with Logain was a recipe for disaster? Last I checked, she met with him, asked him what he would do if free, and then freed him at incredible personal risk. At the very least, that saved the Black Tower. In the long run, it probably was the most critical act that's going to bring the Black and White Towers together.

As for other rulers, the only interaction that I found questionable was with Roedran. As for Tuon... yes. Not the happiest of meeting points there. But most of that was Tuon being an insane sociopath. To be sure, Egwene took the bait when Tuon offered, which perhaps Cadsuane wouldn't do, but she gave back much more than she got. We never know with Cadsuane... she might just have decided to spank some sense into Tuon (and I would have loved that, mind...).