Well, maybe an unusual combo, like more blues and greens mixed in with your neutrals.
Show more metal or at least something that has a futuristic look to it, because that really sells the idea.
And I know there's plenty of it out there, but take a look at the artists that are doing fan art for Doctor Who, and a few other sci-fi arts. More as references rather than to just copy. Since the show itself Is about time travel, it'll help.