Star Trek: Deep Space Nine created and introduced the world to many fantastic new characters. From guys like Benjamin Sisko to women like Kria Nerys to fancy Cardassian spies like Elim Garek and even the scheming Ferengi Quark. Deep Space Nine was so impressive in their ability to create and explore dynamic characters.
One character that fans latched onto was the young Ferengi and nephew of Quark, Nog. Nog, the son of Rom, was following in the same footsteps as his uncle for the longest time. A schemer just like his uncle, Nog's friendship with a young Jake Sisco would help open the young man's mind and see the endless amount of possibilities that could exist for him.
This led to him becoming the first Ferengi to join Starfleet. Not only that, but he played a key role in the Dominion War, serving aboard both Deep Space Nine and its designated ship; the Defiant. In later expanded universe stories, it's revealed that Nog wasn't just some member of Starfleet but that he was one of the best engineers in the entire Federation.
Taking after his mentor, Miles O'Brien. With Star Trek expanding the lore of its franchise through a variety of new avenues, films, animated series, and the like, it would be awesome to see Nog continue and grow as a character in an animated followup to Deep Space Nine, or just a series that includes Nog some point in the future as he's grown into himself.
Sadly, for that to happen, the folks at Star Trek will have to recast him. The man who played Nog so brilliantly, Aron Eisenberg, has since passed away. Making it impossible for Nog to be brought back by the same actor. While things like AI do exist, it feels hollow and even scummy to suggest that Star Trek do that to bring Nog back.
The only real option is recasting him. Nog is a great character, but he was only as great as he was because of Eisenberg's ability to bring him to life. Sure, someone can probably do the same, but will Star Trek execs be patient enough to find the perfect follow-up to Eisenberg?
It's a risk and one that fans may reject wholeheartedly. So for right now, it may be best to just continue to focus on Nog in comics and books, until such a time where a story featuring Nog demands to be made. Then we can revisit the question.