Since the agent portal has a feature to sort replies and comments by date (most recent or oldest), it would be nice to have this feature for free in the agent portal.
To expand further, when you visit the customer portal, what you see is the oldest message on the top of the webpage here:
What is missing is a way to sort the messages in any way, this is rather incovieneint for customers with very long threads and hundreds of messages. They need to scroll all the way to the bottom of the page to see the most recent response in this view.
Furthermore, a customer could sort their tickets by oldest - newest or vice versa. As you can see below, this feature exists for tickets in the customer portal, but not for replies.