Natural Doctrine got off to a rocky start in Japan with poor scores and weak sales. The western release should at least be off to a better start, assuming it incorporates the new patch that's out in Japan. Update 1.03 for Vita and PS3/4 reduces the games's toughness on the easy mode, which has been the cause of some complaint. Presumably, it is still a right bastard at the harder levels.
The patch also adds improvements to online play and adds a pair of co-op missions. Here's what to expect from the quirky RPG. See the Vita version in action here.