1. Actions in haste can bring about destruction.
Many events in the story happen because of the impulsivity of the characters. Tybalt promises to seek revenge on Romeo because he's quick to anger when Romeo shows up at the Capulet party. Romeo is quick to kill Tybalt after the death of Mercutio. Juliet is quick to kill herself (even though she just pretends at first) when Romeo is banished. Romeo is quick to kill himself when he hears that Juliet is dead. Juliet then actually kills herself immediately after seeing Romeo dead. All this death is destruction.
2. Juliet is actually weeping over Romeo's banishment.
Paris thinks that Juliet is weeping over Tybalt's death, but really it's Romeo's banishment because of Tybalt's death. Paris thinks that Juliet is to distraught to think of love and yet the person she thinks of is her love.
3. A nurse claims to be too tired to give Juliet Romeo's message.
The nurse drags out the message she brings back to Juliet by saying she is so out of breath she can't deliver the message. Juliet tells her if you have enough breath to tell me your out of breath you can give me the message! The nurse keeps delaying because she enjoys the attention she is getting from Juliet.
4. Juliet's beauty shines like the sun.
It's Shakespeare, he wouldn't use this beautiful imagery to simply say that Juliet is standing at the window...there's always more. Also, Romeo is in love with Juliet, his descriptive language is used to show how his world revolves around Juliet, his sun.
5. By comparing Juliet to a flower, Capulet emphasizes that she is too beautiful to die.
In the lines, he describes the flower as sweetest which shows its beauty. The flower is not shown to have any age so this eliminates the second best option.