Story: Dream Land is nearly in complete ruins as a mysterious attacker lays waste to the once peaceful Planet Pop Star. It is revealed that Kirby was already doing whatever he could to fend off the invading menace. But to no avail did he succeed, as the attacker used a final devastating blast to send Kirby soaring far away. With Dream Land in trouble, the defeated Kirby must travel through several worlds in order to return and take down the unknown entity who threatens the land. The fate of Dream Land, Pop Star, and the entire universe rests in his hands yet again...
Gameplay: Kirby's new adventure sets him in a completely 3D environment, featuring platforming, puzzles, and challenges for him to face along his journey.
While the levels themselves follow a linear path, the size of the stages would allow for a bit more exploration via sub-areas and branching paths.
While plenty of enemies lie in wait for Kirby's arrival, Kirby also has the ability to talk to certain NPCs within stages (with "..." over their heads) and accept tasks, missions, and challenges from them in exchange for collectibles used to progress through the game.
Tasks may include odd-jobs such as Mint Leaf Raking and Apple Picking
Missions may include minigames such as Wheelie Racing
Challenges revolve specifically on the utilization of certain Copy Abilities for assignments such as "Clear Piles of Snow using the Fire ability"
Bosses: While staples like Whispy Woods return with a trick or two up their sleeves, new baddies connected to the mysterious destroyer try to defeat Kirby themselves. Each boss has multiple phases, with each phase bringing something new to the Boss's arsenal and making their inevitable defeat slightly more difficult to achieve. By defeating bosses, Kirby gains objects and items for use towards defeating the Final Boss.
These are just a few of my base ideas for my ideal 3D Kirby game.