I would agree with you - the conclusion should leave readers with an important thought at the end.
This thought should never be new, or opposing to the previous ideas you had been writing before. It also shouldn't be confusing, but quite conversely - it should explain everything and put everything in place.
Simile and imagery
Hughes is using simile in this poem to compare what happens when you put off dreams. He compares deferred dreams to things with very strong sensory imagery like drying up "like a raisin in the sun" or stinking "like rotten meat". These details help the reader understand the heavy impact of what will happen if you put your dreams on hold.
Answer:
“The thing is - fear can't hurt you any more than a dream.” and "I’m frightened. Of us. I want to go home. Oh God, I want to go home."
Explanation:
I'm not sure if you're looking for specific ones but here are two that I think are the most important/symbolic.
my favorite villain is Hannah baker. she is a rival to Hannah butcher who works at the delicatessen across the street, who is the hero. hannah baker has been accused of lying about the deli meat, saying that it is spoiled, while really her eggs that she bakes with are spoiled and she still sells them.