Well, charity: water took an alternate route. Once someone donates to a charity: water project, her money takes a long journey. Most charities don't tell you about that journey at all -- charity: water uses automated emails to show donors how their money is making an impact over time. With the project timeline and accompanying table, you don't even really need to read the email -- you know immediately where you are in the whole process so you can move onto other things in your inbox.
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.