The reason it seems so natural is because that key has been used for that function in other games. That raises the question, \"Do we try different key configurations or do we use what we know works?\"
Either way, make it functional. The most used keys are grouped together. In FPS games, key assignment is critical. Granted, a MMORPG is no where as near as fast paced, but key assignments are still critical. You dont want to pop open your inventory when you meant to execute an attack.
Thats my 2875 cents.