You kidding me? Perhaps not Epic Yarn, but Mass Attack fit well within the spirit of the Kirby franchise. You may not have taken copy powers or inhaling, but Canvas Curse as you mentioned was fantastic even though its method of taking powers from enemies was different and the method of movement was unlike anything Kirby had ever seen. Mass Attack was a fantastic breath of fresh air and it shouldn't be punished for not including a well-loved part of Kirby only introduced in its second game.
I get what you're trying to say. You could say many a variety of inane babble and I would probably get the gist of it. The problem here is that your criticism is arbitrary. Why is Canvas Curse poor for its use of touch controls? Why is Mass Attack poor for its use of multiple Kirbies? Conversely, for what reason is Kirby's Adventure not poor for regular dependence on these new power-ups, or Super Star for requiring a mostly linear completion of its eight "games"? Or 64 for requiring you to mix and match the proper power-ups to proceed in the game? Or Dream Land 3 for requiring the proper combo of power-up and animal helper to proceed?
Neither of the games you alluded to have game-breaking flaws as a result of their gimmicks. The games were built from the ground-up to work with the stylus and Mass Attack was built from the ground-up to require multiple Kirbies. It's not a flaw of the game to be drastically different. Squeak Squad in particular stands as one of the worst Kirby games for its lack of ingenuity and overuse of older concepts. People who dismiss games solely for being different are just a huge bug; same reason why I can't stand a lot of Phantom Hourglass'/Spirit Tracks' critics. Criticize the games for their poor maps and other flaws, but the touch controls at their very worst are simply "not ideal". They were very well-done for what they were trying to do.
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