It's developed by Next Level Games who have next to no experience in creating a deeper high-quality title. They've either released rather simple games such as Punch-Out and Mario Strikers, or they've created low budget games that haven't fared too well with reviewers. Be happy that Nintendo gives them some more time so that the game does not turn out like their latest console release; the team does not have too much experience.
Well, once you put it that way, I completely understand :/