Left 4 dead 2 b-ball bat

L4D2 Characters from left to right (Ellis, Nick, Coach, Rochelle)

I hope we all agree when i say that when the target is bigger it is far more easier to hit correct? I have noticed that during the demo videos that i have seen Coach is about twice the size as Ellis or Nick and i see him more as a friendly fire hazard due to the fact he is big as hell so far i came up with the idea to limit Coach's aggro so that less zombies focus on him and if not i hope that valve will atleast let him slip by some damage from friendly fire such as taking in half because he is twice the others size. It is quite a disadvantage to the fact that you look at Ellis and he looks as skinny as a scout from Team Fortress 2 and we got an average Nick but Rochelle is a stick. Whatever they do i wish they dont make his hitboxes smaller than his character really is so does anyone have suggestions on how to make Coach a far more pleasant character to play as?