Y'know, I quite enjoyed NJoD. And NiD. I even re-bought NiD when it was cheap for the PS3 (shame that Christmas NiGHTS doesn't work properly).
NJoD does have quite a lot that NiD doesn't - different objectives and styles of play. I didn't mind the platforming parts of NJoD, which NiD glosses over completely. In Christmas NiGHTS I used to love playing as Sonic, and NJoD allows me more platforming action in this world.
NJoD has one MAJOR pitfall though - that, when flying in normal stages, you can't keep going after you've got the key. You can't do multiple laps to push your score further, which is something I always loved about the original - trying to get combos, keep them going and rushing back to the start point when time was getting short. I'd try not to keep any seconds left, often making it back with a single second left. Unfortunately this is cut from NJoD.
Which is, I think, because they couldn't build the traditional platforming engine around it well enough. The kids, on their own, can do some platforming, but only in a small area near the cage. They can't leave this area (except in the platforming levels themselves, which are also restricted) and go jumping around the level, as they did in NiD. In NiD, if NiGHTS ran out of time, the kids would resume play which was fine, as the entire level could be played as the kids (admittedly it wasn't any good though). Here, I think they were striving for a higher quality and couldn't maintain it as the kids, so had to curtail it.
I will have to revisit NJoD at some point - I've now got a Wii U set up, but unfortunately even though I used the GC controller for it, I can't play it on the GamePad. Bit of an annoyance as it would work fine on there, but hey ho.