PS4 and by a large margin. I don't agree with OP points favouring Wii U.
Points 1, 2 and 4 are all the same and are base of flawed logic. N64 audience =/= Wii U audience. Those who own both platforms (Wii U+PS4, presumably a fair portion of Wii U owners by the time this game is out) will mostly go for the PS4 version due to better graphics/performance.
3. Nintendo fans buy Mario like crack*, lets not ignore how mediocre knack has outsold every non mario platformer on Wii U. If anything the abunance of quality exclusive platformers on Wii U versus the PS4 will work in the PS4's favour.
The fact that a late release of Rayman Legends on PS4 > the original, hyped Wii U release should be clear enough indication that PS4 will take the sales crown easily.