Assets are indeed a problem, either expensive, or bad. I altered my basic DAZ clothes in ZBrush, but that's not perfect, hence my choice for MD.
But the humans in my case are made from just the one Genesis 1 basis (which is free), which has morphs for fatter, thin, muscular, etc. I have found some more morphs on the internet, and I made some myself in ZB. So you can make plenty of characters!! Perhaps also if you have access to another modeling software, you can alter the face afterwards, or before and save as morph, etc.