My favorite idea for a unique Up Special is Lip raising a platform made of blocks, 6 blocks wide and a few blocks tall, from the first spot of ground below her (or the bottom blastzone, if she's offstage). It'd have a quick rising animation, then stick on the screen for a set amount of time before popping away. During the rising animation, it'd boost Lip with a big jump, or launch opponents upwards with substantial knockback. While sticking up and before starting to disappear, it could be used as a solid platform by anyone. The downside is that you wouldn't be able to use it again while the previous platform was still around, and since you couldn't do anything to speed up its departure you'd be out of luck if you got yourself into a tricky situation.
Recovery would be interesting, as you'd have a mix-up of either regaining your normal jumps or timing it for one half-screen leap. Used offensively, being able to attack from far below you would keep your opponent on their toes while they're trying to juggle you. Spawning a platform by the ledge would force a hanging opponent to either wait it out and lose invincibility or try to recover high and risk getting punished. There'd be a lot of fun to be had in teams as well, since you could both help your partner recover or set your opponent up to get comboed. Problems could arise when multiple Lips stack their block platforms on top of one another and end up creating a death pillar, but they'd be fun problems to have.
Raising your own blocks to get combo material is an important mechanic in Panel de Pon, and while I'm taking liberties to make it work in the context of Smash I think the emphasis on situational awareness would still be true to the series.
