I'm mixed on this game.
It presents a good concept that can utilize the DS touchscreen very well. It also presents a unique setting that can be used for telling some unique story.
It is often fun and engaging.
However it suffers from some incredibly poor pacing at times. The overworld and level structure offers a ton of promise that is never delivered on properly. Mechanics for traversal and planning your team properly to balance traversal and capture abilities are rarely utilized.
There are some moments of incredibly poor ideas, like an escort mission where your little npc getting dived by an insect in a narrow corridor forces you to start over.
And the difficulty spikes in this game are intense, rarely have I seen such drastic and mandatory spikes.
Also awesome how the game has a quicksave function for saving anywhere, but it's that silly power down the system immediately quicksave. Why not just let us save anywhere then?

Idk, this game was really fun at times and has potential it fails to really utilize well.

An extremely competent kirby game. The new powerups and the touch screen inventory are fun ideas, even if they don't always work in concept. I cannot say there's any super poor level design, or that I didn't enjoy the overall gameplay.
However, I wish that the game was more difficult than it is. Kirby games aren't difficult games, but especially compared to the games following this one, it felt way too easy for most of its run. Having a Kirby final boss, an absolute cosmic abomination, be easier than almost every single boss is downright shameful. Soundtrack isn't as particularly memorable as other Kirby games either, although the Squeak's theme is pretty great.

Great game, I just wish it was better.