It's 100% completely usable for that purpose. To the point where I'm internally using Godot as a backend for my engine, using it for rendering/system events. I

It's 100% completely usable for that purpose. To the point where I'm internally using Godot as a backend for my engine, using it for rendering/system events. It's also really good for a hybrid setup where you use their editor to design scenes, and then you can load/instantiate the scenes at runtime how/when you want. Or, just programmatically creates scenes yourself from code. You can really do whatever you want.