For ejamer, I believe the situation could be something akin to an NES Remix-esque function. Drop players into an iconic moment of the game, such as vs. Ridley from Super Metroid, only give them a healthy amount of Super Missiles and Energy Tanks. Or throw you into a particularly challenging platforming section of Yoshi's Island.
That's how I would like to see this idea implemented, anyway. There is a potential failure in this, which would be "Mario, Link, Kirby, Samus, and that's it". And that the selection of sequences is bullshit like world 1-1 from SMB, which every self-respecting gamer has played, or giving Luigi and Bowser the same scenes as Mario. However, I would like to see them do something with more recent Amiibo characters like Shulk, Robin, and Olimar. We'll have to wait and see what the extent of this service is, though. But hey, more cool **** for Amiibo collectors.