The Wiimotes are not required for any Wii U titles. Those are mostly for the original Wii games. However, I know some games, like NSMBU, does let you use Wiimotes.
Some games like ZombiU, require you to use the gamepad. Assassin's Creed uses the gamepad to display the hud, but you can use a pro controller if you want. Right now, the only games that require the gamepad, that I know of, are ZombiU, and Nintendo Land. The Rabbids game might, but I am not sure.
I already answered his question.... and Just Dance 4 on the Wii U does require the Wiimote.