I've been thinking about that A line skirt - I've never made one!
I don't think they are the most flattering shape!
I have a skirt with an elasticated waist and it is very comfortable, I haven't had any problems with it riding up or folding over. I would want a longer length skirt, though, I think.
I agree with you about dress forms - there are so many variations between women and their individual proportions, I'm not sure a dress form can truly replicate any individual. I've read about adding padding to the form for curvier proportions, but there are some things it is difficult to adjust for. But anyway, it might be easier to be able to hang a garment on something vaguely woman shaped to work on :)