Your buyers regret is why I don't buy anything other than batteries, a case, and a tablet holder when I buy into a drone system.
Drones, especially Autel drones, aren't really like anything else on the market today. They have a very limited life (2yrs is the average according to one study that I read awhile back), they are expensive when compared to many other things that last longer, and even if you don't crash your drone with two years, with Autel you will be unable to get batteries within 3yrs (if history is any indication of the future).
That's why I would never buy a smart controller, or filter kit, or range extender...etc. They are just expensive accessories that you are buying for an ecosystem with a very short shelf life.