I think you are way too optimistic given the install base of Wii U, as well as its current future prospects. Wii U will pick up, but this sort of numbers indicate a nearly 100% attachment rate, and this is not going to happen. Wii titles in these series sold very well, but given the customer base, they still sold well sort of any such percentage -- most big Wii titles had an attachment rate below 30% and this is not going to be any different.
My predictions:
Super Mario 3D World- Low point: 1.7 million | High point: 6.1 million | Most likely: 4-5 million
Mario Kart 8- Low point: 4.5 million | High point: 11 million | Most likely: 6-8 million
Super Smash Bros 4- Low point: 2.8 million | High point: 8 million | Most-likely: 5-6 million
Zelda Wind Waker- Low point: 1.1 million | High point: 3.7 million | Most-likely: 2-3 million
Sonic Lost World- Low point: 0.6 million | High point: 3.4 million | Most-likely: 1-2 million
X/ Xenoblade 2- Low point: 0.4 million | High-point: 1.5 million | Most-likely: ~1 million
Bayonetta 2- Low point: 0.3 million | High point: 1.2 million | Most-likely: ~0.75k
Pikmin 3- Low point: 1 million | High point: 3.8 million | Most-likely ~2 million
The Wonderful 101- Low point: 0.3 million | High point: 0.8 million | Most-likely: ~0.5 million
Donkey Kong Country Tropical Freeze- Low point: 2.1 million | High point: 8 million | Most-likely: 4-5 million
