Honestly playing Kirby Star Allies on your own without any friends or CPUs makes you realize how barren the game actually is.
It definetly explains why the development of the GC Kirby game didn't went smoothly, hell it was even stated that they had problems with the multiplayer, and if im honest i don't think they quite solved it for Star Allies.
But honestly having the ability to play as Gooey, Bandanna Dee, Magolor and Adeleine turns what is otherwise an unremarkable game into a fun adventure and love letter to Kirby's cast. But the level design and ESPECIALLY the lack of set pieces, short level list (only 4 worlds, with the last level beign called World 5) and lack of new unique locals (compare that to Robobot's far more interesing level settings such as a City, Robot Factories, a Casino Level and even an Ice Cream factory) means that i do agree with the view that this game is the low point of the Modern Kirby game Tetralogy (Return to Dream Land, Triple Deluxe, Planet Robobot and this one)