Adjusting the Starting Common Items in Arkham Horror

I am one of those individuals that loves the potential for a good story from my games. Consequently, I am drawn to those games, such as Arkham Horror, that just exude theme. Unfortunately, a good story can become derailed at the beginning due to some minor inconsistency - some feature which manages to pull one out of one's suspension of disbelief. Speaking personally, this occurs on a fairly regular basis during the set-up phase of Arkham Horror when the random items are assigned. Many are the times that I have wondered why my Magician character would start the game with a Time Bomb, rather than some Dusty Manucripts. And why on earth would a doctor have a Tommy Gun and a supply of Dynamite laying around his office?