Use the precise word you need to accomplish your goal. For example, is your heroine a pretty woman? A beautiful woman? A lovely woman? Each adjective is positive, but the meanings are slightly different. The connotations that have grown up around these words over the years demand that you know which describes your heroine if your readers are to envision the same woman you do. For example, a pretty woman may not be beautiful, just pretty, and a beautiful woman may not be lovely; likewise, a lovely woman may be neither pretty nor beautiful, but lovely.
Synonyms can be tricky!
Some synonyms for “famous” are “eminent,” “prominent,” “ illustrious,” among others, but you may not mean eminent, prominent, or illustrious if you mean famous. You may, but be certain, as the meanings convey important shades of difference. And by all means, if you mean famous, don’t use infamous. That in- prefix negates the former positive meaning. Use your dictionary to find the word closest to your meaning.
Some words that we tend to use freely are not needed at all. For example, more than once, I have seen “very unique.” Unique means one of a kind, unlike anything else. Using very to indicate a degree of uniqueness is redundant. Something is either unique or it is not. Period. In fact, experiment by removing “very” from your text everywhere you find it. I think you’ll see an improvement in the flow of your writing. Now do the same with “really.” Some writing teachers—and writers—advocate eliminating every adverb. I don’t go that far. Sometimes they are useful. However, experiment with your text. Be exact!