I agree, and actually the same can be done the other way around. You can create a React component that handles 99% of all your Three.js code then just have that

I agree, and actually the same can be done the other way around. You can create a React component that handles 99% of all your Three.js code then just have that and this UI used together at a high level. Three.js' API is great for 3D programming but creating UIs suffers the same problems as creating UIs with plain JS in the DOM. Also, no need to feel sorry! This is just an exploration at this point, so it's interesting for me to hear peoples' reactions whatever they may be.