Setting up a new mac/iphone without transferring all of my data?

Hey everyone, wanted to figure out the easiest way to go about doing this.

Just purchased rMB upgrading from 2010 MBP. I chose not to transfer all of my files to the new computer as I don't want to be cluttered with old files I will never use again. My question is: what is the easiest way to transfer a small number of files (mainly my iTunes library) to my new mac?

Also, can I sync my iPhone to my new mac w/o deleting iMessage content, notes, etc? Is there a way to make an iPhone backup on my old mac, transfer it to my new mac, and sync that to my iPhone (essentially passing the torch?)

I guess I can always migrate everything over and delete what I don't want, which would be time consuming but probably not have any problems. Which cable would be fastest?