I'm sorry but I still don't understand why it's better to use both swipeDistance + swipeVelocity instead of the existing swipeThreshold. I'm actually quite open to remove the existing swipeThreshold in favor of using those 2 variables, but I don't want to keep both mechanisms unless you have a very good reason.

The current swipeThreshold mechanism include the velocity in a more accurate calculation whereas your approach is simpler. I'd prefer to use the existing mechanism if possible, just kicking it in earlier.