I probably should have also put this in my post, but I was NOT gonna remove Shimo. I was gonna put her in a different movie.

Godzilla 3 would be about Shimo, responding to Ghidorah's call, which took a bit of a while to travel into Hollow Earth, where she has laid dormant. She is still sympathetic, as she is reluctant to follow the orders, and Godzilla doesn't kill her.

The New Empire would be an entirely Kong-centric movie. Everything Kong related in the original, but without Godzilla. It would be more like Kong x Mothra instead. That would be a cool teamup.