I suggest adding a feature so that the date/time is logged for each time that an email is opened and each time that a link is clicked. Also, if there are multiple links in an email, track date/time that each link is clicked. Provide the same information for email attachments This could be reported as a summary in the Email table for each lead page or contact page. A detail for that email would be available by clicking on the email to access a report for the Opens and Clicks.
I use Bananatag, and this feature is available. It offers additional valuable information. For example, if there are several products that are offered in an email, and a lead clicks on one of the product links multiple times, but perhaps does not click on another product link at all, this will provide insight on the interest of the email recipient. Also, if the email is opened many times, it would also indicate higher interest.