It could be an old acquaintance from his past who has turned to the dark side. Maybe someone he once trusted during one of his earlier adventures but who has since become jealous of Drake's success and wants to use him to get rich quick. For example, a former partner who was left behind in a previous treasure hunt and now blames Drake for his misfortunes.
One plot idea could be that Nathan Drake is kidnapped by a long - lost rival who believes he has the key to a hidden treasure. The rival takes him to a remote island. Drake then has to use his wits and knowledge of the area's history to escape and turn the tables on his captor. He might find clues within the kidnapper's lair that lead to a greater mystery.
One possible plotline could be Nathan dealing with the aftermath of an injury that affects his ability to adventure. He might have to rely on his friends more, and there could be a lot of internal struggle as he tries to come to terms with his new limitations. For example, he could be haunted by memories of past adventures while being unable to fully participate in a new one.
Nathan's hurt could force him to re - evaluate his life choices. Maybe he starts to question whether all the risks he's taken in the past were worth it. This self - reflection can be shown through his internal monologues and conversations with other characters. He could also start to mentor a younger character, passing on his knowledge while also learning from their fresh perspective.
I think Uncharted Story is good. The way it unfolds keeps you hooked, and the settings and action scenes are well-done. But, of course, it's subjective - different people have different standards for what makes a story good.
I don't really know who Nathan Bartlett is in this context. He could be an ordinary person whose story is being told, or perhaps he's someone with a unique or remarkable story.