creative writing...
first of all, viewpoints:
1st person - this is a PERSONAL viewpoint. you need to characterise the voice you use. if you do not do this, your story will not work. if you(as the persona) are emotionally attached to what is happening, you must show this. if your person is dumb, they cannot be writing 15 letter words and eloquent descriptions.
2nd person - this viewpoint is hardest to achieve. probably best to not dwell in it for the entire story. can be used in small amounts within one of the other two viewpoints to evoke thought and emotional response to effect(through making them question their own life). it is confronting at times.
3rd person - if you want to write in a way that does not suit the character you are portraying(this must still suit the story) use this. it also allows you to expand the responders view without the character knowing these things. it is less confronting and immediate than the other two viewpoints, so empathy will need to be worked for.
think about what you are writing. there is no point in using image saturation if it takes away from the concept of journey* you are trying to convey. perhaps if it is to contrast with the brevity of something, or call attention to a specific element that is vital in your story, image saturation is called for.
but honestly, if you choose to write a 1st person story from the viewpoint of a pre-teen with brain damage, you cannot be writing as if you are(trying to be) a novelist with a university qualifications.
dialogue should be used sparingly. also, find many words to use instead of "said" - cried, exclaimed, whispered, shouted, wailed, etc. - because dialogue must be dynamic. try to use dialogue as aural imagery if you can - give them clues as to the voice. is it growly, nasal, or childlike? what do the words sound like?
figurative language is good - but only if used correctly. dont force it into your piece if it shouldnt be there. it will take away, not add to, your writing.
try not to use the "this and that" formula.
eg: "she was confident but modest. her eyes told of happiness and sorrow."
bad example, but still it could be changed to: "she held an aura of quiet confidence, her eyes creased at the edges hinting at a life of happiness, their depths telling of a seemingly paradoxical sorrow." or something.
also, DONT change the tone of your piece halfway through, unless it is part of the actual story.