It’s hard to imagine a 64x64 texture would cause a visible chug. It’s possible, but I think it’s likely to be something else that’s making the chug.
By chance are you using the auto-shader with something like render.set_shader_auto()? That would require a new shader to be compiled the first time a particular render state is encountered, which would indeed cause a visible chug.
Unfortunately, prepare_scene() doesn’t yet handle pre-compiling shaders. I agree it should, but it doesn’t.
David