A while ago I started making Latin and Greek readers for myself in the style of Lingua Latina, mostly so I could read about the Church and the saints while practicing the languages. I decided to publish one of my Greek readers, despite Amazon giving me trouble.
It's Athanasius's Life of Antony, with the harder words explained in Greek in the margin, the way LLPSI does it for Latin. I had created these in a similar format because it had helped me when I was learning Latin and became comfortable with readers in that style.
It's meant for anyone who has worked through a bit of Athenaze or taken a course in Koine. Athanasius writes a plainer, more literary Koine than the Gospels.
There are free sample pages on the site if you want to check the level before picking one up. I'd love to know what you think and what you'd want to read next in this format.