The beautiful thing about imagination is that it's limitless.
As a writer, allowing your imagination to run wild might be the best move you ever make.
Start big and different and fresh and risky and then worry about the details later. Words can always be revised and refined and rethought. But, if you don't stretch you mind and let your imagination live freely, then you'll miss all those original ideas that are locked in your mental treasure chest.
It's not that the crazy ideas you come up with are THE ideas. It's that the crazy ideas will fire up your imagination and get you to THE ideas.
And that's what we need! Original ideas that make readers want to know more.
It's like being in a valley and not knowing what's on the other side of the mountain. If you don't climb the mountain, you'll never know. Every step up the mountain is like a new idea. With each step, you get closer to the top, and with each new idea you get closer to THE ONE. When you get to the top of the mountain you don't see what you thought you were going to see. You thought you were going to see another valley like the one you just came from. Instead, you see...hell, I don't know...vampires playing baseball.
The point is that with every new idea comes new possibilities. So don't limit yourself.
Let your imagination flow...no matter how ridiculous things might get!
It's so much easier to look at a hundred ideas and notice the one sticking out, than it is to look at just a few.