Lave the burn the way it is. Reduce Ammo count back to 5 rounds, reduce reload speed back to "Slow-as--blam!-" Thorn only became a plague in the Crucible when it became easier to use by the (for lack of a more appropriate term) scrubs. I had Thorn back in the day, and while it was still just as deadly as it is now, it was a hell of a lot harder to actually be of much success while using it. You couldn't just spray bullets all over the place with little to no consequence like you can now. Bungie pretty much took the only "balancing factors" of the weapon (Low Mag, Slow Reload) and completely trivialized them because too many people felt that Thorn was too HARD to use. Now, it's weapon of choice because it's literally become overpowered and user-friendly. SO... While Bungie's overreaction is partially to blame, the community criers are infinitely more responsible for the imbalance.