SD1.5 + SDXL Base shows already good results. SD1.5 + SDXL Base+Refiner is for experiment only
SD1.5 + SDXL Base - using SDXL as composition generation and SD 1.5 for final work
SD1.5 + SDXL Base+Refiner - using SDXL Base with Refiner as composition generation and SD 1.5 for final work