You should have different approaches when you migrate low- and high-value and low- and high-risk information. Much depends upon the cost of your migration tool, how organized the content is and who “owns” the content.
If you’re undertaking a migration from network drives to Office 365 or other similar tools, make sure to invest some time in defining the information architecture for that new environment—i.e. how the documents you migrate are going to be organized in the new system.
Some ideas for how to address the complexity of the myriad applications within Office 365, to help manage technology governance, regulatory compliance, records management, and electronic discovery of the content created in those applications.