Based on all the information we have gathered during our in-depth research we assign a magic score to each vendor. This is based on factors that affect any solo ad purchase (for e.g: CPC, Sales, Conversion rate etc). We use our proprietary algorithm to do this. As a rule of thumb, higher the Magic Score, better the solo ad experience is going to be.

Location: Businesses that offer local service, such as a lawn service company, obviously need to target local customers, but regional, national, and global companies can also benefit from location-based personalization. Consider running special campaigns for customers in a specified location based on regional events or what’s happening at your local office.

You might consider making the language in your alt text actionable, such as "Click here to download the ultimate content creation kit." Actionable alt text will essentially turn every linked image into another CTA. So, even if someone doesn't see the snazzy GIF of my latest offer (or if they hover their mouse over an image that does show up), the alt text will beckon them to click.
When it comes to deciding how to craft that perfect subject line, there appears to be really only one area to avoid: the subject line of 60 to 70 characters. Marketers refer to this as the “dead zone” of subject length. According to research by Adestra, which tracked over 900 million emails for its report, there is no increase in either open rate or clickthroughs at this 60-to-70 character length of subject line.