Inspired mainly by Star Control and to a lesser degree Star Wars as well as Vangers, I've begun imagining creating a space opera game in which you interact with aliens through screens (similar to Star Trek as well, as to how ship captains would interact through view screens.)
The real difference would be in how each alien would be represented in a completely different technique - humans might be live action actors, while a friendly species might be portrayed like the Yip Yip Martians from Sesame Street, while an evil alien might be a hand marionette in the style of Barnaby Dixon, while others yet might be made of clay or other animation techniques, maybe even old school 8 bit graphics or more modern and familiar techniques.
Could be cool to have different freelancers work on different races, and see what they produce with loose briefs, then try to create the actual spaceship game objects in a similar visual language.
Also have some thoughts on the actual game itself, and combat in a truly 3D environment, ships slowly maneuvering to bring their guns to bear in similar fashion to naval tactics in the age of sail. Have I written about that before? I've had the idea for a while.