Just make a simple list. Year 1, the Wii U had Pikmin 3, Nintendo Land, NSMBU, 3D World, ZombiU, Monster Hunter, WWHD, and a few more I might forget (ignored most 3rd party games that didnt really affect the Wii U).

Year 1, the Switch is getting BotW, MK8, Spla2n, Skyrim, FE Warriors, Mario Odyssey, Sonic, Arms, Xenoblade 2, plus a few unanounced games.

So, Wii U had: an RTS game, a party game, 2 platformers (2D and 3D), survival-horror, and action-adventure games (1 a port, another a remake). And do consider the 3DS already had a 2D and 3D Mario not too far off from the Wii U launch.

The Switch will have: an action-adventure game, racer, 3rd person online shooter, WRPG, whatever Warriors games genre is, 2 3D platformers, a fighter, JRPG, and a huge amount of indies.

Simply by genre variety, I'd say the Switch wins. But also consider which IPs are releasing with the Switch. A new 3D Zelda (last one is +5 years old), a Mario Kart 8 port (3 years old), Splatoon sequel (best selling console game from 8th gen in Japan), TES V (onf of the most popular games of all time), FE (recently revived and super popular series; although it's a spin-off), sandbox 3D Mario (last one released on the GC), 3D Sonic (eehm... we'll see), new IP (we'll see), and sequel to XC (pretty popular on the West. Not very succesful though).

Of course, we had this kind of topics with the Wii U. A pretty long list of games that would "save the Wii U", so it's not a success by default. But having a good first year is, in my opinion, crucial to modern gaming. The Wii U had horrible droughts, no indie games, no VC support, horrendous OS, high price, and zero marketing (because of droughts) in it's first year in the market.

The Switch could easily avoid all that (except price), it's all up to Nintendo to not be idiots and support their system correctly. Since the Switch going forward will be their sole system to support, it will be impossible for it to get doughts. All they need is to have a succesful first year.

Didn't expect to rant for this long.

Not one of these "loyal Nintendo supporting" Japanese developers could bother to even have 1 console-caliber title available for the entire launch window? 

That's pretty sad. 

Then I guess you're knowledge is limited cause ZombiU,Pikmin 3, HD port of Monster Hunter 3 Ultimate and a sidescroller 2D Mario ain't gonna save that launch window (Someone already did a post explaining that issue) when you go at face value against a brand new 3D Mario sandbox game, Splatoon 2, Xeno 2, Fire Emblem Musou and a port of MK8 with a new battle mode. And we still have Directs and E3 to go.

Backward compatibility is not something the mass market care nowadays ( This argument has no weight anymore )