Merging/Moving iTunes without using migration asst

I have maybe one of the most bizarre, confusing questions that I hope some genius out there can help me with.

I currently have two machines: an iMac and a Macbook Pro. Both are running the latest versions of all software including OS X.

Currently my iMac is my "primary" machine in that it's the hardware I use to sync my iPhone and iPad (I don't use iCloud for backups as the storage capacity is too low). It stores all my music, movies, apps, etc. I also use it randomly for web browsing, etc.

In terms of a true "primary" though, my Macbook Pro is, in that I use the mbp for Applications, Documents, Photos, etc. I use this machine for web development, my photography business (processing/selective image archiving, etc.), and basically everything else, on a daily basis.

My dilemma is this. I just want to move all my iTunes stuff to the mbp and use that as the primary hardware for managing/syncing my iPhone/iPad because at some point I want to get rid of the iMac. It appears Migration Asst isn't the right tool for this as the step just before transferring asks about creating a new home folder username (both machines have the same home folder name, my first name). I don't want two accounts on the mbp; I'd just like one account as I have it but with all my data vs using one machine for syncs and one machine daily as my primary. The iTunes app on my mbp is clean so there just has to be a way I can move everything over without corruption??

Pipe dream: I'd like to retain all meta data for my iTunes library... it's over 7 years old with lots of customizations.

Thoughts?

Thank you!

Christine