While I agree that losing aggro is anything but simple i've yet to have a problem other than it just taking some time, if you're near an accessible building its easy but out in the open you have to get their attacks in time with dropping LOS. I generally find atleast one weapon before I get anywhere near a zombie, just knowing the best areas for guns to zombie ratios near the start, Rog and Zub being 2 of the easiest places to gear up depending on your spawn.
Loving the new Double-barrel shotgun, useless at range but hilarious in buildings. Someone tried to sneak behind me after I warned them in chat earlier so I hid beside a door and placed the barrel on the side of their head as they walked in, instant free beans .