This feels like a really cool gimmick with a lot of potential, it's so unique and can add so much to battles ! The one thing I would add is pretty much what other people have said, that being adding an option to not completely remove rng (at least the one involved with a Pokémon's focus), but even then it makes sense that if you're gonna have a way to proc these events, you shouldn't be able to both have them be random and determined at the same time.
I really hope this is brought back to 21.1 someday, as from what I've seen it doesn't seem to be planned at least for now. Still a really great plugin overall.
This plugin was always more of a proof of concept for me, anyway. More of a showcase of what I would do to solve Pokemon's RNG issues if I was the one in charge at Game Freak lol. The fact that I made it at all is enough for me; I made my vision a reality. That was always more of the point of this plugin for me, and less about people actually using it for their games. That's why this feels kinda "done" to me, and I feel little incentive to rehash it again with a port.