If you're not in the mood for a rant stop reading now.
I know this is something that noone else would want to spend time on, but, it sure would be nice if the meshes were normalized so that a point on the body stays in the same place on the body as targets are applied. The most obvious illustration of the issue is to turn on the grid in MH and watch the grid on the lower back slide around as you morph from female to male. Why it is a problem can be seen by putting, for example, the tight jeans from the repository on a toon and then sliding back and forth between female and male; the back top of the jeans gets distorted as it follows the grid which is distorting. And it's not just the back that changes, a straight line around the waste will get distorted with individual vertices being moved up or down. And it's not just male/female morphs, as you increase the muscle slider on a male toon a straight waistline will take on an upward curve. There are many other random vertex movements but at the moment I'm focused on the waistline because it so drastically ruins clothing that could be unisex, as well as making it look bad after other morphs. I spent a lot of time on a speedo suit today but it basically only looks as intended on the "average male" toon.
While I'm ranting, something else I ran into today, when you narrow the hips the top half of the thighs also gets narrowed, but not the bottom half, so you get a bottom half that bulges out in a very unnatural way. And there is no other target that counteracts that. Hmm, looks like it was just scaled with proportionate editing turned on. It would have been much better to use the armature and scale the hip bones.
The really depressing thing is that even with the will to fix them they won't be fixed in order to be backward compatible. The saving grace is that one can create their own targets for their own use, although that requires any user contributed stuff to be adjusted to match before you can use it.
There, got that off my chest.