Version 2.1.0 adds Botania pixie chance support, vanillaCrit gamerule (defaults to true), which will prevent vanilla (falling) crits when set to false (for use with Zenith Attributes crit chance attribute).
2.1.0 also removes the hard requirement for Spell Engine, but I am not sure if there are any other use cases for this mod. Additionally, when Zenith Crits happen, Botania Will crit effects should activate.