Could you please consider adding a rule to adjust spawning based on moon phase? Specifically I'd like to limit spawns during a full moon but increase them during the new moon.

The phases are detailed at http://minecraft.gamepedia.com/Moon, and it looks like you can retrieve the current phase with world.provider.getMoonPhase

Thank you :)

Cool, will add.

Done. Please check https://minecraft.curseforge.com/projects/no-mob-spawning-on-trees

Perfect :) Thanks!