My main inspirations are: Elite, Starlancer, Freelancer, Wing Commander and Morrowind. The main factors of these games that I love are the depth, setting and lore, and free-form game-play. You want to go there? Go there. Make a life, get a job, earn credits/gold, upgrade what you want, help who you want, kill who you want. See that ruin? Read about it's past glory days in a book in the library in your home town. Ultimate freedom of choice, ultimate passive storytelling, ultimate immersion possibility.