Add email to CRM record button

I’d like to add to this - not just contacts and companies but deals too. Often times I work with people who effect multiple deals but I don’t want to add them to the deal. I want the ability to add just an email from them to a deal. Currently this can be accomplished by searching for their contact record, finding the email, and then adding an association to that email only. But why not have this ability right in the Gmail integration? The edit option in tracking only works as long as tracking stays on the email thread. If for any reason tracking stops you lose the edit option.