I think the hats should be named without "Hat" at the end.
Having commands such as "/hat TreeHat" is redundant; I already know that I'm going to be wearing a hat that is a tree because I took the time to type /hat before it. Hats such as the Tophat should be excluded from that, obviously, but I think PresentHat, TreeHat, etc. shouldn't have "Hat" at the end.