To ensure Northern Trail Outfitters' sending reputation remains intact, implementing a Sender Authentication Package (SAP) with a Private Domain and a Dedicated IP is the best course of action. This setup provides greater control over the sending environment, allowing the company to build and maintain its sending reputation without being affected by other customers sharing the same domain or IP. It also facilitates the use of SPF, DKIM, and DMARC authentication protocols.
References:
* Salesforce Marketing Cloud Documentation on Sender Authentication Package

Explanation
Email Overlay View is the area of the application that should provide the data on link performance for a specific email, including Total Clicks and Unique Clicks. Email Overlay View shows a visual representation of your email with metrics for each link, such as how many times it was clicked, by whom, and when. You can access Email Overlay View from the Tracking tab by selecting an email send and clicking on View Email Overlay. Send Performance Tab shows metrics for an email send, such as Sent, Delivered, Opens, Clicks, etc., but not for each link. Tracking Conversions Tab shows metrics for conversions that occurred as a result of an email send, such as purchases, sign-ups, downloads, etc., but not for each link.