Let me see...one thing.
I would have to say they should have shrunk the levels down vertically, and tightened the controls a ton more.
OK, that was two things. So I'll pick the second one. Better controls. There.
Ya, the levels all have a "diluted" feeling to them, the set pieces aren't few, they're just far between. in NiD, you passed some of the set peices, two maybe three times, in the new game, take a good look, cause you arn't seeing that part of the level again. NiD's levels felt more like actually places, but in JoD, the levels feel way too generic for a NiGHTS game. even though Splash Garden and spring Valley are both a bunch of Green Hills, there's a bunch of other stuff there that get you more immersed into the level.
This post was longer, BUT I'm going to save it for the review of JoD that I've been planning.