The calculation for mu when dynamic_shift_len is provided can be simplified. Since base_shift and max_shift are both math.log(3), the call to _calculate_shift_qwen_image will always return math.log(3). You can directly assign this value to mu and remove the now-unused base_shift and max_shift variables for better readability and maintainability.

        # Sigmas
        sigma_start = sigma_min + (sigma_max - sigma_min) * denoising_strength
        sigmas = torch.linspace(sigma_start, sigma_min, num_inference_steps + 1)[:-1]
        # Mu
        if exponential_shift_mu is not None:
            mu = exponential_shift_mu
        elif dynamic_shift_len is not None:
            mu = math.log(3)
        else:
            mu = 0.8

The LoRA alpha value is calculated as 8/64. While correct, using a simplified fraction 1/8 or the direct float value 0.125 would be clearer and avoid an unnecessary division operation.

The vram_config dictionary is defined but never used. To enable low VRAM optimizations, you need to pass this configuration to each ModelConfig instance. Without this, the script will not run in low VRAM mode as intended.

The LoRA alpha value is calculated as 8/64. While correct, using a simplified fraction 1/8 or the direct float value 0.125 would be clearer and avoid an unnecessary division operation.