When I was in college, I once wrote an extremely self-indulgent story for my screenplay class that I didn't know we were going to read aloud. I was kind of embarrassed, it was a weird story, but another student actually found me after class to tell me how much he loved it. I think that's the first time I realised that if I was really, really into an idea, someone else would be into it too. They might like it for the same reasons as me! And that realisation is honestly the only way Runewriters could have happened.
I'm not really sure how wide Runewriters' appeal could be? I know that when I'm at cons and get to see folks face-to-face at least, the readership seems to trend towards teenagers and some young adults (which, given where the main characters are in life, makes sense to me). But honestly, almost every decisions is made based on what I would really get excited about, if I were reading it.