Reducing print temperature and increasing non-printing movement speed will do far more to reduce stringing than any amount of tweaking that you can do with retraction settings. It's a little counter-intuitive at first but the concept is that by reducing printing temperature, less molten plastic will be oozing, and faster non-printing movements means the nozzle is not lingering around for it to ooze to begin with. Those should always be your first two adjustments to fix stringing issues.
After that, fine tune your settings with retraction and wipe adjustments.
If you approach from retraction settings first to combat stringing, I promise you will go crazy. And still have strings when you are done... Temp and movement first, then retract and wipe settings and you can get down to angel hairs or gossamer on even the hardest torture tests.