I think I could agree with your placement of Summer Salt, but I wonder if she's better than we think. Per tear, an opponent loses 3% health every second, yeah? So with a well timed Napalm shower, especially while the opponent is getting back up, they could easily lose 9% health. It seems like keeping them in the corner is the best strategy, between the Napalm Shower and the two tears you can get from a juggle combo. Plus, those diamond stats and Critical mass are a big help. Maybe Primed still deals more damage - I'm not sure as I don't have Summer Salt - but she may be at the top. This is just speculation though, if anyone with Summer would like to shed some light on this.