Picture this:
Smash Direct: One Week Before the WiiU launch
After a nice 25 minutes of WiiU stages, modes, trailers, etc, it cuts to Sakurai again, wearing a parka.
Sakurai: "I've received many complaints from fans about some of their favorite characters missing from the 3DS version. Please understand, certain decisions had to be made to allow the game to be released as soon as possible for you to enjoy, and this included difficult decision to remove certain characters from the roster. However, with the additional resources and time for the WiiU version... well, just take a look"
Trailer starts on Lylat Cruise. Falco and Fox fight on the ship, a battle behind them. On the radio, suddenly, Wolf! "Ha, Star Fox, you didn't think I'd really let you get off that easy" Wolf jumps off a Wolfen that was flying close and a video of him fighting. This lasts about 10 seconds, until out of nowhere "PK FWEEZE!" Lucas, jumps down from off camera, 10 seconds of Lucas. Then, Ice Climbers! Some time with them.
The video ends on Mario Galaxy, Ice Climbers vs Roy Koopa and Sonic. It pans back slowly. We see Bowser's airship in the back. Wait... As it zooms into the ship, a box is on it? A box!? It raises up "Miss me?" Snake montage, confirms Shadow Moses Island as a retro level on the WiiU.
Cut back to Sakurai: "We've worked incredibly hard to bring you these characters to the WiiU version. Don't worry 3DS Smash fans, these characters will also be appearing in your game in a free content update, later this year. Thank you for watching, I hope you're enjoying the 3DS Smash Bros, and are eager and excited to try the WiiU version.
...
Smash Bros logo, slashed with fire
Chorus Boys trailer!
Ends with a note about how they will be available on the WiiU day 1, and on the 3DS by the end of 2014.