Okay, this is all pretty tenuous, but super interesting: apparently, a Sega of Europe employee kept a blog last year in which he revealed some stuff about NiGHTS: Journey of Dreams that he shouldn't have, well before the game's release. The posts have since been removed, but the Wayback Machine allows us to have a look back!
According to the blog post, Journey of Dreams was originally developed as an Xbox 360/PlayStation 3 title, and was hastily shunted to the Wii when the platform's success became obvious -- despite protests from director Takashi Iizuka. The 360 version was at least far enough along to be playable! The quick change in plans meant that NiGHTS' development time was effectively shortened. If you didn't like the game, you have something on which to blame the problems!
Also interesting, if this blog post is really as vintage as it looks (we don't discount some kind of Internet trickery): the blogger dropped a pretty big hint about a future Sega game, saying that Sonic Team should be freed from Sonic games, "... before they release another Sonic game with a transforming Evil 'Night' Sonic who looks like a werewolf and can stretch his arms out Dhalsim-style. It will happen, mark my words."