Well we were mainly moving to new structures so the migration was two part, moving recent data to a faster server and the older data shifted to cheaper archive storage. SSIS was utilised in very simple form, a data flow with source, destination and lookup tasks were the main components as well as script tasks for some customisation. Lookup tasks are very handy for incremental loads as you may be doing.

Highly recommend you give this a read if you havent already: http://www.sqlservercentral.com/articles/Stairway+Series/76390/

We didnt have enterprise otherwise I would have implemented some form of partitioning for sure.