Two steps forward and two steps back
Ni no Kuni is the most divisive game I've ever played. Many elements are done either well or good enough, while just about as many are done terribly. On one hand, Studio Ghibli contributed some of the best visual design I've ever seen in a game. The monsters, characters, and different settings all feel like they were ripped out of a animator's cell (do they use those anymore?). The Pokemon-like familiars system where you level different creatures to fight for you is really fun and addicting even when most of the second/third forms of the familiars are more palette changes than full on transformations. The soundtrack matches the amazing visuals -- not surprising considering that Joe Hisaishi has scored every notable Studio Ghibli film. But these are sadly the only "perfect" elements in Ni no Kuni.
The story is nothing to criticize or praise. It serves its purpose and that's it. Don't expect surprising twists or interesting plot points unless you're an easily surprised individual. Besides Oliver's fairy, Drippy, the characters are a bit flat and in Oliver's case, a bit too "Golly Gosh/Gee Whiz!".
The gameplay is where Ni no Kuni slips up. Most encounters play out like an improved version of Final Fantasy XII's real time combat system, and in that regard it's an almost enjoyable experience. However, once you fight anything more than standard trash mobs, the entire system starts to fall apart. Everything about it seems like it takes one extra, unnecessary step. For example, to switch from one of Oliver's familiars to a party member's healer familiar and back requires these steps: L1 -> select Party Member -> L1 -> select Familiar -> use ability -> L1 -> select Oliver -> select Familiar. Each of those steps also has a cooldown period, rendering multitasking to be almost impossible, and if the AI was competent this would have just been a minor complaint. Instead, the AI walks a tightrope between functional and rage-inducing. Your party members seem to heal only when they find it convenient and seem to follow the same logic when it comes to attacking. Unbelievably, you get the ability to block with all your party members 15 hours into the game. That's 63% of a full day or two Call of Duty campaigns. Up until that point you can't do anything about enemy attacks or boss abilities - you just get hit.
Hypothetically you should be able to manually select every party member and defend with each one, except that doesn't work. The second you deselect a character they will revert back to doing whatever the abysmal AI wants to do. This, combined with vague boss moves, manages to be extremely frustrating ("do I block now or do I block now" - there is no clear answer usually), and often are the bosses in Ni no Kuni scaled way too high in comparison to the mobs you encounter on the way, with mechanics that never feel clever or well though out. It's as if developer Level-5 couldn't be bothered to increase difficultly without just going "Screw it, make the numbers higher".
This trend of inconveniences seeps into every single aspect of Ni No Kuni. For one, Oliver uses an assortment of magic spells to solve puzzles during the story. This works until the game insists on piling spells on you at every major plot point, reaching a point where you have 15-20 almost useless abilities that you've used to solve one puzzle and nothing else. It's a waste of time and potential. Another small nitpick is that you can't just use story-specific magic without going through a dialog window. For instance, to magically conjure a bridge you have to walk up the point where a "?" appears above Oliver's head, press X, read the dialog, then select the applicable spell from your spellbook. I personally think it makes more sense just open your spellbook when "?" appears and select from there, but that's not even an option. Did anyone outside of Level-5 bother to playtest this game?
You also might know developer Level-5 from the Professor Layton games, but you couldn't tell from the puzzles featured in Ni no Kuni. For a game to have so few puzzles, yet have them all be uniformly terrible is an achievement by itself. Seriously, go to Google and type "Ni No Kuni Frog Puzzle". Trust me, it's no spoiler. It's almost an art form to have puzzles that bad. It's an abomination of game design to make a puzzle artificially difficult by using misdirection.
In the end I couldn't forgive all these problems, and trust me, there's more than the ones mentioned. I found the combat more frustrating than fun, the story didn't hold my interest, and the game's only saving grace: the art design and familiars system couldn't mask the flaws. Ni no Kuni consistently takes two steps forward and two steps back throughout its 45 hour main story. Yet even with all these problems present I felt compelled to finish the game. So something is definitely here -- too bad it's weighed down by questionable game design.