The question

I am so sorry for the delaying in answering your email. Is there another way of saying that can make the sentence more in balance? Can that make the sentence easier?

Are you asking if the word "that" can make the sentence more in balance? Depends, on how you use it. The word "that" is used as a pronoun or an adjective. 

Dear Yun Duo. This is infact a question so next time please make sure u post stuff like this in the question section. Thanks.

The question

I am so sorry for delaying answering your email.is there another saying that can make the sentence more in balance?Can make the sebtence easier?

Instead, u could write: Please accept my apology for replying late to your email.