come on Dex... GET GOOD, SON! No, Just kidding. Honestly, always having anywhere from 3 to 15 more agility than str, and just playing in general, I've come to realize that unless I've got a long spear or something similar, with which I can do combat while being out of combat (long pole arm or a ranged weapon), my team is my biggest enemy. If Agi builds are good at anything, it's avoiding the enemy. Translates to: Stay the hell away from your team.
That, and be a kill stealing bastard. Sprint in, overhead, dodge out, move on.