I've been ruminating (love that word) on what makes good, easy-to-read, beautiful writing. Mostly, this is due to my own current stage in the writing process: revising a manuscript for the third time. I think I've fixed most of the big-picture ideas, and now have only to work on issues of style and voice.
Style according to French writer and filmmaker Alain Robbe-Gillet:
"The true writer has nothing to say. What counts is the way he says it."
Voice according to English novelist and clergyman Laurence Sterne:
"Writing, when properly managed, is but a different name for conversation."
One how-to article will tell you to show actions creatively, while another author might be convinced that internal monologue is the way to filter just about everything your point-of-view character is experiencing.
One writing manual will extol the virtues of simplicity in language, while another will preach fresh and inventive prose as the only way to stand out from the crowd.
The way we choose to say our theme, our character's thoughts, his actions, and our villain's dastardly deeds--it all comes down to choices.
So as far as your word choice goes...
Use the word said. Just not too much.
And use the word dastardly. But only once.
Use conjunctions, commas, double-dashes, and sentence fragments. for. dramatic. effect.
Just don't do these things ad nauseam. Moderation in all things.
Above all, be true to your own voice, and to the voice of each character. After all, we write to share. The language needs to facilitate that, never inhibit it.
Focus on writing the tightest plot, most relatable characters, and on telling the story that lives in your head. Then revise it. Ask others to read it, and hope their insights will help you realize that you typed "blustering" when you meant "blistering", or "said" when you meant "screeched". But don't anguish over the perfect language. I fervently believe that voice and style are things picked up like accents and slang--through communication. So read and write. Write and read. And stop stressing about perfect words. They don't exist. There are only people, personalities, and preferences.
Isn't it wonderful?