I have to admit I prefer my Mario games more linear with things to explore inside the level, and this game has a nice balance. Instead of worlds each world is just 1 level, and it isn't even huge. But they are packed with content, secrets, easter eggs, everything. I spent nearly 5 hours in the first level alone just exploring and having fun. Combat isn't really there, outside of sometimes you taking control of things (you can mindcontrole enemies by putting your hat on them, but only if they don't have a hat).
It is a really smart mechanic, as you can always spot what can be possessed by their head. Does it have a hat? No? Then let's go! Some bosses are all about you removing their hat and striking, it is really cool how they made it an emphasis. Your ship is even a hat which has a lounge where you drink coffee from hat-shaped cups. It is adorable.
I could talk for hours about the beautiful art design, packed levels, sometimes too packed levels, costumes, jokes, easter eggs or just how damned complex movement can be if you want... it really is insane. What's great is that Nintendo rewards this mastery and going bonkers. There are a few situations where, by smart usage of the mechanics, you can get 'out of bounds' or reach areas that you probably aren't supposed to get to. And there are coins there. It is really cool to see you get rewarded, feels like someone really broke the game apart and instead of fixing it, they put coins where they found glitches or out of bounds like that.
My favorite thing though is very minor, but I never ever see it in games. And that is good idle animations. If you stand idle on a couch, you'll sit on it. If you stand idle on a bench, you'll sit on it. Stand idle next to a radio and Mario will listen to it. Stand idle for too long on the grass and he'll fall asleep. Sleep long enough and a bird will sit on your nose, this bird is different per level to fit the style of that level. Stand idle next to a band and you'll dance to the rythm. It boggles the mind just how many animations there are in this game and I love it.
My favorite moment is when you first fly away in your ship, and during a cutscene you are sitting in your ship drinking coffee with your hat.
My first instinct was to, after the cutscene, go into the ship and sit on the chair. And it worked. And my hat came off and he started reading, looking at things etc. These things always happen to me in games where I hope they will happen, but they don't. But this game actually does those minor things I love so much.
I do have to make a little comment about the controversy on the game. Apparently the whole feminist sector hates it, since Peach is the victim again having to be saved by Mario. This makes me go: