There are two ways of looking at AOW, and one of the big variables is the instructor.
Many people who have just finished their OW class have pretty rudimentary diving skills. Some are pretty uncomfortable in the water -- I know I was. For such people, the AOW class is a way to do five more dives with an instructor for insurance and security. It isn't possible to absorb a great deal on any of the topics, because staying alive underwater is still a challenge, but you do pick up a few things. Honestly, I think this is what the class is DESIGNED for -- sort of an "Open Water II". If it is taught to minimum standards, then it may not take long before independent diving would get you to a point where you would feel the class was pretty worthless.
The other kind of AOW is taught by instructors like NW Grateful Diver, and is NOT taught to minimum standards. This can be a really challenging and useful class with a lot of good information in it, but it is not a class one should take straight out of OW. You would need stronger basic diving skills than most people have at the end of their certification, to do such a class justice.
The business model for scuba instruction is to sell ConEd. Shops and instructors typically make very little, if any money from OW students, but the returns increase significantly when students come back to take specialty classes. For this reason, they are often heavily pushed.
Since you have already had some experience with this instructor, I'd sit down and look at the AOW book, and ask yourself if the instructor added ANYTHING to what you could get out of reading the book and then going diving. If your answer is no, then don't take any more classes, at least not right away. If the instuctor was truly adding value -- helping you significantly with the physical skills of diving, or providing additional information, then you may choose to take the class soon, if not right away.