The Pure Swing is not symmetrical, so the observation you had would have more to do with the type of roll a 4 inch pin to pap creates on an asymetrical core as opposed a symmetrical one.

A 4 inch pin to PAP on an asymmetrical core ball would give you good mid-late hook, where as the 5 1/2 inch pin on the Wild Thing puts the ball for max flare just at the end of the pattern. Just looking at this the Pure Swing Should hook more overall, but the Wild Thing is probably stronger down lane.

What is the drilling angle? Val Angle? What are your specs (Revs, Speed, Tilt, Axis Rotation)?

the drillings on your balls is the determining factor.  the placement of the pin to your pap is a bid deal on how the ball rolls and reacts.  I have both your balls the pure and the wild thing.  The fact is your wild thing has the longer pin to pap placement which is why it seems weaker than the pure.  the pure however is a very versitile ball and can handle heavy or light oil depending on release.  
My two balls are very similiar in drilling. Both are stacked leveraged on the left side(I'm a lefty) one is up and the other is down.  my pure is the up pin drill and the wild thing is down drill.  the main difference with these two is the wildthing picks up a touch sooner on the lane before it snaps to the pocket.  The pure I can aim down lane and through strait there before it just changes direction and goes to the pocket.  the pure is close to a skid/snap ball and the wild thing is similiar but has midlane move added.