How about a way to have them as both self-focused and targeted? Use the skill and a gyro hovers around you. It flips into a ground targeted skill which will tell the gyro to stick to a location instead! Then you can adjust the self-targeted version in WvW to be useless, and the ground-targeted version can have the full effect!
Also please revert Specter nerf, it's entirely unwarranted in pve and, frankly, wvw as well. I played a bit in wvw and a lone guardian could strip the entire shroud bar in less than a second...