You should avoid the overuse of exclamation points because you'll appear to be
A. shouting at the reader.
B. showing off.
C. exhibiting bias.
D. creating confusion

To be honest, all of those sound applicable. But since there isn't an all of the above answer, I'd say your best bet is either A or D. 

I would say A because not only can you sound exited by using them but in novels there also used when people are angry