Versions are useful as they allow switchover functionality enabling a user to both enter a forecast on a line and see actuals in the same line item. However, comparing versions to eachother (any version to any other version dynamically) requires a "Versions List" and logic to engage that list with the Version you want to pull with [SELECT:VERSIONS.(verions name here]. If Version could be a format of a line item, then Anaplan reporting out of version would be greatly enhanced as these version formatted line items could be used in Lookup statements.