If you're planning to farm older raids for the weapons, do it with a hunter. They can wear any weapon type beside shields, making them extremely efficient at unlocking the skins. Now I know many of the more experienced players know about this, but because melee has been removed and only recently reintegrated, it's easy to forget/not know.
If you haven't preordered legion and didn't have any specific class in mind for the boost, you may want to spend it on a Hunter. Considering this and the global spec rework, it's the best time to also level one if you didn't before (Marksmanship is amazing).
EDIT: Warriors are less efficient, but as Rotted pointed out, you can get all weapons too - including shield and maces!