I just wanted to understand one thing here for Pardot syncing, what happen when I unverify the connection and migrate data into Salesforce? does this migrate all the leads/contacts from Salesforce to Pardot automatically when enable connection again?
The connector does not create prospects retroactively. If you use the setting 'Automatically create prospects in Pardot if they are created in Salesforce', those prospects are created only after the connector is installed and this setting is enabled. This is what pardot documentation says about this:
Pardot creates a prospect when a lead or contact with an email address that is not already associated with a prospect is created in Salesforce. An email address is required on the lead or contact record to sync to Pardot. This setting is not retroactive and creates prospects only for those leads and contacts created after this setting has been enabled.
However, if this feature is enabled later on, then leads and contacts with email addresses that were created after the Pardot package was installed in Salesforce will be pushed down to Pardot. So when you reverify and you have not removed the Pardot package from Salesforce, Leads and Contacts created in the meantime will sync.
Alternatively, create a report of all new leads and contacts after unverifying the connector, and add these leads and contacts to a campaign in order to push those campaign members to a pardot list after reinstalling the connector.