I almost forgot the worst bug of all. Blend2 and Blend3 animations don't smoothly blend for custom mesh animations created in Godot. My imported Mixamo animations seem to blend fine, but for some reason as soon as I try tweaking the animations they no longer blend and instead jerk to the target animation only when the blend value crosses over to a 0 or 1. This happens with blend spaces as well as blend nodes. Right now, it seems quite impossible to create a custom 1d blend space look up/down animation because of this issue.
All of the previous bugs are just inconveniences, but this is seriously interfering with my ability to make the game I'd like to make. I can't model or animate so being able to create animations by simply modifying bone transforms is very important to me and to others i would imagine.