Paranoid_Penguin The easiest way to migrate would be to create a Seedvault backup and restore on the new phone. Seedvault isn't very good (which is why the developers want to replace it), but I've heard that enabling device to device (D2D?) makes backups work a lot more often.
You may want to keep your old phone around for a while to make sure everything worked as expected, so if anything was missed, you can transition/move the remaining things manually.