Glad you are having fun! Grats on getting the 6-6-6 luck ;)
As for making your own content, here's my quick-and-dirty guideline:
🔲 Credit and link back to me on the store page + in the book
🔲 Consider having your game be pay-what-you-want with no minimum (just like One Page Left)
🔲 PLEASE. Please. Do not include content that would make me look bad by association, for example One Page School Shooting or One Page Genocide may seem like "fun" ideas to some people but I really don't want me and my game associated with that!!
And have fun! If you need any help please feel free to hit me up. I'm pretty active on social media and my discord. Who knows, if I really like your concept I might even make some art~ 😉