Update: They could easily include 3DS style Miis in future Wii-U games, even allowing Wii games to be enhanced to use the Wii-U Miis as the parts are read from the system, not the disk...
...The Wii-U Mii Channel could allow newer Miis to be used in older Wii games, allowing more variety in characters, and humor, and could allow up to 150-200 Miis instead of the usual 100.
Anyways, what future game series do you think should link 3DS games and Wii(U) Games together, and still use Miis in both versions?
"Warioware 4D"/"Warioware: 5 Ways 4 U 2 Play"(Touchscreen, mic, Tilt, trigger buttons, camera, Wii Remote Motion Plus & Nunchuk)Audience laugh track plays
Or Mario Kart 3DS/Mario Kart Double Dash Deluxe/U Double Dash Again!
(Wii-U & 3DS contain both New and Retro courses, while 3DS can only play the Wii-U version exclusive Battle Courses in 3D when connected to Wii) Up to 8-10 players when 3DS connects to the Wii-U, and track sharing features allowed through 3DS download play with Mario Kart 3DS game card,
Both Single Kart and Dual Kart Modes, plus motorcycles, as vehicles, and Tag Team mode added.
They would have multiplayer games that link the two systems together...
...especially since the controls for 3DS is only missing Dual-touch, triggers, and one control stick....