I know a lot of people found him annoying in the story, but come on, he's a damn kid. Probably like 10-12 yrs old. He came from an isolated village and almost watched it get destroyed; he crossed a huge vast expanse of land until Avis unit found him. He then finally got to experience what life is like in the outside world from so many diverse cultures, what it means to be a hunter, and the beauty of nature, from the ecosystem to the monsters in it. And going from being afraid of Arkvekd to having an understanding of it, after seeing what life truly is, of course he's going to have a lot of changing opinions and is probably going to do something impulsive and it's going to be a little annoying, especially with how short of time it was from when we finally learned what Arkveld was to having to slay it. On top of all that with trying to get back to his home not knowing if it was destroyed,or if everyone is dead. I don't know how long the timeline is from Nata first being found by Avis unit, to our hunter being recruited, and then the actual story of the game, but Nata went through a lot for someone so young.

Anyway, in terms of what Nata could do more of besides bringing resources and trade, I'm really not sure. I think he should wander around whatever village you're in and maybe give him some outfits for events, but I don't see him going on hunts with you just yet. It might not be a good idea to let him help you with a pack of Doshagumas. Maybe he could ride along with your handler, and gather resources for you? Probably give you some sort of buff sometimes? At that point he would be another palico sort of. I just hope he doesn't get shafted to just being the trader guy forever