So lately I've become a little bit tired of the green menace and want a change. Aside from the melee stomping I also love ranged tactics with battlelines full of guns that riddle down the enemy from afar. Right now I'm equally interested in SM, Tau and Skitarii. I think all models look nice and am just wondering how do their ranged-orientered armies differ and what is their ranged advantage? Which is "most" strategic?