Ironically, I don’t like games (films, books, and whatever also) with time travel as its main theme.
But nothing can fit to everybody’s taste. Trying to create a game based around other people’s liking isn’t a very productive way of creating games, >>3705
is right in that you should create a game to your liking, following your own interests, and then some people will like it while others won’t.
I advise you to plan the story, characters, environments and everything else, at least to a basic level, before actually starting to create the game. If you’re thinking of working on the game right away and that the planning will occur to you as you go along then you’re going for a harsh surprise, and chances are you’re going to give up on the game before even completing half of it.