Hot coffee and hot tea are also available. Personally, I did not like the coffee at all.
Generally, the Always Included makes sense if you drink a good amount of alcohol.
At embarkation, you are also allowed to bring on a couple of bottles of wine and while I have not been able to find the details however, I think you can bring on a limited amount of soda.
If all you have that is addition is the occasional espresso drink and a glass of wine or cocktail occasionally the AI is not worth it. However, there is a convenience in having the AI.
On a recent cruise we did AI and enjoyed it but probably drank more alcohol than we should have. The next cruise we booked decided to do cruise only.
There are great long threads going intricate detail of when it does and does not make sense to get AI.
Additionally, the AI includes gratuities that are quite high on Celebrity so that has to be taken into account.