You can take full control over the design and sending of your outbound emails and messages by using Klaviyo.
Ensure you've connected Klaviyo to Glu first.
Why use Klaviyo?
You can send WhatsApp or SMS instead where appropriate.
You have full control of the email design and content.
The messages can look and feel inline with your other marketing communication.
Create the relevent flows in Klaviyo
In Klaviyo you can setup flows that are triggered by events that occur in Glu, those events include the information relevent to the event that triggered the flow so you're able to include that in your message designs.
If you've setup a flow in Klaviyo to handle outbound communication, you need to ensure that Glu is not setup to also send out a message or the customer could receive two messages, how this is done will vary depending on what flow you have setup.
Things to note
Sending messages via Klaviyo in this way does use your normal Klaviyo sending limits and spend, depending on your usage and plan it may increase how much Klaviyo costs.