Lines in Poetry

What are the things that make you choose the length of your lines in your poetry if you are not using a set classical form?
What do you know about using lines to enhance your poem?
Here are somethings I have learned.

Can you add to my knowledge 

Always read your poem aloud to understand where the breaks need to come.
Line breaks are like rests in music a  pause for breath

Very short lines add doubt… suspense

Irregular … sudden rhythm

Short ….nervous energy

Broken syntax ….makes reader focus

Enjambment …..forces the reader to focus on the last word of the line

One line…. fluidity
Line breaks can add sound, music and tone

They can also help creating the emotions of joy, horror or sadness
Where should you make your line breaks?

You need to read it aloud to get the feel for the piece and get the break in the right place

If using enjambment if you are using comas read it aloud to check the coma is in the right place and not forcing a stop where none is needed.
Getting your line breaks wrong can make it difficult for the reader.