I don't think you'll find anyone that will disagree that they would've preferred Minion Park from USJ or even USH's area - but sadly, UO put themselves in a corner with Minion Mayhem to Production Central. It's easier playing Monday Morning QB though, as I don't think you'd find anything in 2011/2012 from anyone suggesting Universal should wait and make Minion Mayhem a signature land.
So within the parameters, this land can still succeed without the need for having the level of immersion of Potter or Nintendo.
Also keep in mind, we still don't know the extent of how the finished product will look.