Make it scannable. Your subscribers are busy people who get a lot of email, so it's safe to assume you don't have their undivided attention. Instead of one long block, break up your content into short paragraphs. Include subheadings and images to guide readers through your email and make it easier to scan, and add a teaser to the top of your newsletter to tell subscribers what's in store. If you're sending a long article, consider inserting a "read more" link so people can get to the rest when it's convenient for them. Your subject line should be to-the-point and easy to digest, too. You might even want to a/b test subject lines to see which ones perform best.
Customers demonstrate the potential to become more valuable customers. These are profitable when assessed in terms of lifetime value, but the number of product holdings or current value is relatively low compared with the group above. Recommendations about relevant products based on their purchasing and browser behaviour can be an effective approach with this segment.
This article is by far one of the most interesting and fun articles that I have read in a long time. I say fun because the points mentioned here are simple and easy to read. They are not long passages that speak a lot and tends to lose focus. On the contrary the points mentioned here were in short crisp sentences that did not bore me but made my read a pleasurable one. Thanks!