Message Validation & Canonical Translation

Hi

  We have a requirement where we receive 8 csv files and translate into canonical message. I have some questions related to validating source message.

1. Dissemble Stage: I have written a custom pipeline to handle any csv (dynamically load schema details) to an xml. 
2. Validation: I’m planning to write one more component to validate source message against the schema but what’s the best approach? Should I validate in the pipeline or translate the source message into a canonical message and send into a message box and calling a .NET component to validate the canonical message inside a orchestration which subscribe to a message?

1. Another question I do have is, is it best practice to let the custom pipeline to translate the source message into a canonical message (XSLTTransform .NET)  Or call translation (Map).  If translation then which stage do we need to call and it should be dynamic