I've always seen scouts and rangers as being more of a reconnaissance-oriented class, sneaking about amongst enemies, remaining hidden until striking. That's why I'd like to suggest some manner of Camouflage ability/spell/line of items that scouts and rangers use.
The effect of Camouflage is to make yourself harder to detect. Really good camouflage renders someone invisible until you're almost on top of them. Translated into the game mechanics, Scout/Ranger Camouflage would reduce the aggro radius of various mobs. Naturally, if you fire a round into the head of a mithril golem, it'll aggro and come after you, so Camouflage would have to be a non-combat function.
A similar ability or spell could be given to spellcasters of all races, only this one, "Mirage," can be used in combat. Mirage is an AoE debuff, with short to medium range. When cast it offers a certain percent chance of causing an attacking force of mobs to go after a mirage, instead of a player. The mirages look like ghosts (human, sslik, ghostly dragons, etc) but just stand there until the spell wears out.
In this manner, a single player could appear as a group to the mobs, diverting some of the incoming attacks.
Just a suggestion. What do you all think?