I'm not currently working on writing any new fanfics atm, cause I have a billion wips that I need to finish. But, if I were to start anything new right now, I think it would be something about Jim Kirk spiraling after "Operation: Annihilate!" and dealing with his brother's death.
Maybe bring in SNW characters, show Spock and Uhura and Chapel dealing with Sam's death. Bring up La'an. And Ortegas. And M'Benga. His friends.
Heck, Peter lost both his parents. He almost died himself. His uncle doesn't say really anything to him. He was like, twelve.
Bones would be the only one who didn't know Sam personally, and he might be the one person who is there for a lot of them. (Kirk and Spock mostly. For obvious reasons.) He can see the way Sam touched the lives of everyone around him. The impact of his legacy.
Basically, if I were to write anything completely new right now, it would be a very angsty story about everyone being sad over the death of George Samuel Kirk Jr. Because Sam deserved to be mourned.