How do I shorten validation time?
I think that your OLE DB source is causing the issue


Create a new table with the same schema as your current source and point the component at it.  
Within the package, update to your actual source, as this will force it to handle it at run-time.  The easiest way I have found to do this is to create a variable and assign it to the source expression.  See an example of this at https://stackoverflow.com/questions/18288183/parameterized-oledb-source-query


Another possible solution is to set the DelayValidation property of the Data Flow task to True - See https://technet.microsoft.com/en-us/library/aa337088(v=sql.105).aspx#Anchor_4