I love having access to a dress form. It's not really adjustable, but just having something to put what I'm working on over makes it so much easier to have accurate results. I think I could learn and do a lot more if I had access to dress forms in every body type - but they costs hundreds of dollars, and I don't have space for that many dress forms.
There are inexpensive ways to make your own dress form. Put on an old t-shirt, get a friend to wrap you up in duct-tape, then sew and stuff it. Voila! Dress form! These are great things, but as far as I can see, having access to a personalized dress form will only teach you to make clothes for yourself.
Something I think that would be really valuable for folks who can't afford a range of body type dress forms would be miniature adjustable dress forms. I'm assuming that, once research and development was done, something like that could be made for a $20 price point.
I'm going to brainstorm ways this could be done.