There's a great lack of content compared to other Kirby games, it's very short, some of the copy abilities just really suck (and losing them every single time you get hit is annoying), it's pitifully easy, the bubble system has potential but the fact that treasure takes up space means you won't be able to carry much and will constantly have to toss out things to make space, the game has a frustrating tendency to place treasure down one of two (or more) branching paths with no indication which way is the right one, forcing you to play the level over again if you missed it, and the story and general presentation aren't particularly memorable.
Despite all of that, though, I can't find myself disliking this game. It controls excellently, with a sense of speed that no other Kirby game I've played has. The levels are super short, which compliments that sense of speed, and is also generally good for a handheld. No wonder it has a built-it speedrun mode. Looking past the few bad abilities (metal, cupid, and I'd even say magic, though that could be more up to preference), the simpler nature compared to Super Star and the more modern series makes it more fun to swap between them as you go through a level, and there's not any one ability I find myself desperately trying to stick onto. It has the best pixel art of the series in my eyes (besides maybe Canvas Curse, though I've not played that one), and definitely the best Kirby dance. The music is great, too (some incredibly memorable tunes and the return of some classic ones as well), though that's nothing out of the ordinary for Kirby. It won't give you quite as lasting an experience as any other Kirby game, but it's a fun and quick (and largely fun because it's quick!) romp through Dreamland.