I redid the world generation, and removed the hard-coded 64x64x64 world size. It is possible now to set the world size to just whatever, and since it's a raycaster, it wont have a performance impact unless the render distance is significantly increased. I'm going to release version 0.4 when I get text working, and anything that I do up until that point (such as this) will also be included in the update.
I've included a screenshot of a 128x128x128 world, with increased view distance to display the terrain.
PS the reason why the screenshot is blurry is due to a bug with processing on gnome, I need to redo the part of the code where it draws the graphics buffer. But I'm using this workaround until i get around to that.