One thing I've been considering doing for a while is "one change for every Smash fighter", with the catch being that said changes wouldn't be restricted to changing moves; I could tweak existing moves, change a taunt/victory animation, change an alt, or throw in some minor easter egg. Hell, I'd say move changes would be the minority in such a list of changes, seeing as most of the move changes I'd make would be accompanied by another change to balance it out, which would quantify as a second change and therefore be ineligble.
There's no April Fool's joke, is there?