I'd be able to answer more specifically if I had more info on your experience and startup, but I can also answer higher level and hope it's useful for you.
Experience - are you deeply familiar with the problem you're trying to solve and the current options for solving it. Have you lived this problem? Have you been a consumer of the solutions? Why do you care about it? Why can you solve it better than anyone else?
Story - the answers to the above question will naturally help create your story. Friends can vouch probably won't hold up.
Bootstrapping - not everyone can bootstrap, but investors want commitment. If you signal any lack of commitment then it will tank the perception of the investment opportunity.
Pilot - do you mean MVP? At seed stage or pre-seed you don't need a product, but having a working demo or something tangible helps make your ideas more real for other people. Having some traction helps them place it in the real world.
Generally fundraising isn't so cut and dry. There's a spectrum of outcomes ranging from getting a great deal on great terms with a great fund that will probably get you in tech crunch, to raising a fine deal, on ok terms, with a 3rd rate VC fund, to failing to raise at all. The probability for better outcomes depends on how well you cover the bases of what VCs actually want to know, but also on how much they believe that you, specifically you, are the right bet for this type of solution/category.
When they invest in you it means they can't invest in other solutions that are similar (they can but they shouldn't and good VCs mostly don't).
Often VCs will already have a thesis or belief about the market you operate in. It will be high level, but they're going to have some opinion about the way the wind is blowing. They take a position on a macro trend and then find the best possible exposure to that trend in a great founding team and vision.