We’re so busy trying not to be bad writers that we forget: there are a lot of bad agents out there too. Sounds like you ran into one, because that relationship never left the ground it feels like. I like idea #1 the most but to me, all of them can work if you’re heart is in them. Which it would be, as you told us!
But in general, I too think most ideas don’t need to be books. And I sure as hell don’t want to waste a year trying to force one into becoming one. So I’ve got time :)