Think as well about the kinds of metrics you're evaluating. You probably know that interaction with email campaigns is measured through open and click-through rates. While it's meaningful to review email response in this way, if this is all you measure, you're missing the bigger picture of the value of email to your company and its customers. These rich metrics in the email are great. However, there is a distinction must be made between:
The downside of just making offers is that they’re not useful on their own. People on your list won’t receive any value from you unless they buy what you’re promoting, so they have little reason to stay subscribed. That’s why this email marketing strategy doesn’t work alone. And it’s why many e-commerce sites struggle to keep people interested. There are a few exceptions (e.g., Groupon) that rely entirely on making offers—but then the reason people joined the list was specifically to receive those offers.
For example, you may analyse the journeys on your website and identify that people who visit a page is more likely to purchase than those who do not visit that page. With behavioural data pointing towards the potential for this page, it would be worth testing whether offering a bespoke content message or discount offer to users when they arrive at that page drives conversions. It could be that your customers have left items in their baskets and not completed their purchase, like this example here from Nordstrom:
Embedding images, animation, and vids in an email are tricky, as these elements often mess up during the transfer from one platform to another. A multitude of email clients, operating systems, and connection speeds make this an area in which to proceed with caution. Videos and animation are undeniably eye-catching and engaging, so it may be worth the risk of a dropoff to include them.
Everyone's busy and their inbox is already full. Why add to the problem with a longwinded email? People generally like short, concise emails better than long ones because concise emails have an obvious focus. Plus, when your users are scanning through all their emails in a short amount of time, they're more likely to find the overall message before deciding to take any action.