If you would give a talk about this, I would watch it - despite being out of the graphics for almost 10 years now. Really want to hear from the trenches about the workflows, benefits and challenges you have.
https://twitter.com/P_Galbraith/status/1649317290926825473?c...
This is using Stable Diffusion and the Control Net Lineart Model. The coloured version is pretty rough but it was a quick test.
In my opinion Stable Diffusion is vastly superior to Midjourney if you have the skill to provide input to img2img/ControlNet.
I have some other earlier workflow experiments on Youtube if you're interested in this kind of thing https://www.youtube.com/pjgalbraith