I am not sure about the budget portion for GameFreak during the release of Pokemon Colosseum as Nintendo was reworking the pay structure and their work with GameFreak around that time.

Colesseum though, I just played it for the first time ever and my god it is hardest and most tedious of the entire series and the music is killer. The underlying narrative and lore is interesting when you start adding XD Gale or Darkness into the mix as well.