Muramasa the Demon Blade as best 3rd party Wii game. Suprisingly long gameplay time if you want to 100% it on the normal difficulty settings with alot of post game content. Then theres that 1Hp mode where you die in one hit which totally changes gameplay and turns it into almost a totally different game, becoming a Megaman-ish like game where you have to remember enemy movement patterns in order to even progress.
Other than that, Little King's Story, possibly my second favourite 3rd party game. A much move colourful and vibrant Pikmin, better art direction, a quirky story line, and some of the most interesting gameplay features.