One thing I've noticed about the vintage figures, especially the ROTJ line, was how realistic the details were. For example, the wrinkles in clothing or other details like skin or hair texture. That was something that didn't carry over to the modern figures, at least not until much more recently.
To illustrate my point, take a ROTJ figure, say Prune Face. Pretend you can blow it up to life size, say 6 feet tall. Now do the same to the modern figure of Prune Face (Orrimarko). If you were to compare the two at 6 feet tall, the vintage figure would look much more life-like, or at least like a mannequin. The modern figure would probably look more like a 6-foot toy.
Not that it wouldn't be neat to have a 6-foot tall SW figure