after beating as much pikuniku as i can, i think i can give my verdict: (mild spoilers incoming?)
it’s definitely not a game you should play in one sitting.
i think it’s best played when you’re in a busy schedule. the busier, the better (though some of the challenges does allocate quite a lot of time). that way the gameplay spreads from a few hours, to a few days, weeks, or even months (if you’re that busy). if you rush it, you’ll not feel the charm as thoroughly as you might hope. the narrative at the end, especially, doesn’t really grip if you just hustle your way on the main route (not that there's any diverging paths besides the five (!) side quests i found, with three just building on another). i really should’ve played it when i was busy on my campus (maybe i will on a new save)
other than that, it’s an excellent game. the soundtrack is superb, it really screams fun and playful (the swamp is my favorite, alongside toastopia). gotta love the accordion and the cuica that appears sometimes. the art design, oh, they nailed that. worthy to be put alongside boxboy in terms of simplicity. and cuteness. =) maybe a little bit more content could be better—a time attack on some of the minigames or something other than the co-op, which is unplayable due to a lack of external controllers—but the game’s fine as it is. i think the additions i suggested would impact the story (and, in a way, the whole philosophy of the game) quite a lot.