I've been doing a play study on character movement in platform games, which sounds really academic, but I'm building a prototype for a platform game which could turn into a mega-awesome WiiWare title, so it's not academic. Pursuant to this I got to replaying two killer titles from my youth, Kirby Superstar and the Ninja Gaiden Trilogy. They're both not quite what I remembered them as, both were promisingly fresh examples of platformer kineticism in their time, and they're both dated in interesting ways. Kirby's series is one saturated in cuteness, softness, and padding: gameplay padding, physical padding, content padding. Ninja Gaiden is a series that is balls-to-the-wall difficult, being legendary among the grew-up-on-the-NES set for its insanely repetitive challenges.
Kirby moves slow, you can double tap or get the Wheel familiar to move fast in some instances, but most of your time is spent waddling around or huffing up and slowly floating. The difficulty level correlates as being very low; most of the extras involve scoring extra lives which aren't generally necessary. After all, gravity is just a timing consideration. These games were among the first in a now all-too-entrenched trend of making games hold your hand and gently lead you through a pleasant theme park of content. But at the time, it was a new thing, so it worked. While Kirby is kinda fat, Ryu Hyubusa is in good shape, and he moves like it. Speeds are constant, jumping and wall jumping is a pre-requisite, gravity is the enemy. The initial game has you carefully timing the y on your sword swings and puts you at the mercy of every hit, taking your control away as the slight peck of a bird will send you kneeling back into a pit. Oddly enough, for a game that has you up against the entire cast of SlipKnot, the most deadly enemy -- by far -- is a bird that does three bars of damage and tracks your movements in 360. The loss of control from hits is one movement shortfall that the two games have in common, although Kirby reserves it for only a few enemies and Ninja Gaiden lays it out from the slightest breeze. Incidentally both of these games also have an edge-of-the-screen respawn dynamic in place, which worked so well for King's Quest players but works precisely against you in Ninja Gaiden, and can be a useful way to copy the powers you want in Kirby. The later Ninja Gaiden games overcome the shortfalls of a narrow y range for the sword (III) and the frozen hang of the wall grab (II, where you can climb any wall); III also reduced the paralysis in being hit by cutting the x delta by 70% and made spawning much looser, i.e. no more killing something while standing still right at the edge of its spawn point and having it respawn immediately.
Kirby comes replete with character designs for each and every enemy, who through a pseudo-Freudian act of eating will convert from an oppressive other to a familiar sort. The simplicity of the Kirby design, in particular, lends it very well to highly iconic emotions. The cards for the samurai, the wheel, the fire character, and so forth all convey more personality individually than a truck full of Ninja Gaiden cut-scenes. Speaking of which, Ninja Gaiden's plot is waaaay stupider than I remember it. Basically there are these wacky demons and then the CIA ends up being evil after you take care of the demons, and your girlfriend keeps getting either threatened or killed but then she's OK. There's always a scene where you're standing on a cliff looking over at this big fortress where the last half of the game takes place, and then at the end you're always with your girl talking about how beautiful the sunrise is. Just get naked already. Kirby's storyline is stone stupid as well, but at least it has the dignity not to take itself so seriously.
Basically a truly next-gen platform game design, in my opinion, would embody the same kind of balance between character design and restrictions on movement while shedding any penalization of controls and making acceleration a lot more analog. The gameplay would also be grounded in a non-linear environment that is procedurally generated ala Spelunky. Maybe I'd keep the ridiculous plot line.