I kinda get what your saying, I will address two points in what your saying however.
The first being the statement that nobody uses them as if that was the case this would not have been brought up
The second is that yes you are right they can be taken as not 'nice' comments but the way they are delivered has been created to keep them lighthearted. There will never be a system that accounts for individuality in servers, it is impossible to create.
I would not object to adding a !ns command as well as the !fu command, however the !fu command will not be removed - if however there are specific sayings you feel are too much then I can look at removing them.
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