Middle Earth creating

Hello, I am about to begin making of the Tolkien's Middle Earth. It is my personal artistic project, simply out of love for this books and it's lore. And I am looking for some engine which would allow me to do this. It means; huge map, a lot of characters, animations, architecture, some voice over (eventually), and quests. Everything based on books. I understand the absurd scale of my hobby, and I mean it as long term, personal project. I am inspired by games of Fumito Ueda, like The Shadow of The Collossus, Ico, or The Last Guardian. I would like to make it more like these games, rather than, for example, Skyrim. Game would be more packed and tighter, with the pressure on mood, atmosphere and uniqueness of the experience, rather than huge army battles and monster fighting. So my question is: what would be the constrains and weaknesses of the Unity engine on this project and where it would really "hurt" me to make it? As (for now) only one person? And for which reasons is Unity good choice for this? Given the fact, that I am aiming on art, mood and minimalism like we can see in Ueda's games, more than battles and AI like in other games? Any ideas?