IDK if the GPL license is compatible with your business, but I wonder if you could package Fooocus or Fooocus-MRE into a window? Its a hairy monster to install and run, but I've never gotten such consistently amazing results from a single prompt box + style dropdown box (including native HF diffusers and other diffusers-based frontends). The automatic augmentations to the SDXL pipine are amazing:
