I play one of every profession, and I enjoy them all. Nothing like going on my elementalist and tearing people apart in PvP using double daggers or a scepter+dagger. I don't see how anyone can say they're underpowered with a straight face. Squishy? Without a doubt. Hard to play effectively? Definitively. Underpowered? Not a chance.
"Ranged" isn't a role. Support is a role. Control is a role. Damage is a role. The guardian can do all three of these, particularly support.