there are some unique loot situations in this game, I agree. However I think you will find at level 50, gear is pretty much designed with just a single spec in mind. In a four man group it'd be rare to have, say, a juggernaut dps and a marauder dps that both want str mods. Most juggs are tanks and go for defensive gear. I think highest priority should always go to a person who can use the item as it is. After that I think 2nd priority would be someone who wants to use the mods, and 3rd would be someone who wants the look. Looks are fun but sadly end-game gear is not compatible with moddable equipment in it's current state, so you will be gimping yourself if you use anything but the end-game set for your class.