please don't make a Bitcoin exchange/bank. or anything that will take enduser's private PII or money.
the mindset to "just go make something" is admirable in some cases. on others it's not. scratching your own itch and then monetizing it is admirable. picking up a knife and thinking therefore that one can be a neurosurgeon now, is not.
too many people do the latter. the former is fine. ;-)
Me, I'd be happy if I could find a little niche to fill, and if it could pay me a very comfortable wage that allowed me to retire in 5 or so years. I'm 38 now - half a million a year for a couple of years, then sell whatever it is for another couple of million, that'll do me very nicely thank you very much.
Does that sound like a lifestyle business? Damn right. That's exactly what I want. (I'm in Australia, BTW - the whole Silicon Valley, work 23 hours a day, all that crap - no thanks. I value my life and my friends at way more than a billion dollars.)
No, it doesn't. It sounds like a 3 SD event.