I think the only way Jabba could be improved in Star Wars is either by complete removal (the way it should be) or a complete re-render and new compositing. Especially considering how well ILM can make a digital creation look and feel like a puppet now, there’s no reason they can’t re-model Jabba so he looks and moves in a way that is much closer to how he looked in 1983 than any of the digital recreations, none of which are all that close, not in texture, not in shape, not in coloration.

Jabba is, like many things Lucas did with Star Wars, a “good-enough” effort, but not the best one.