i think the switch has two issues. one is the price of the accessories and the other is the online component. the online hasn't been clarified yet, but what has been made known doesn't sound very appealing. some of the accessory pricing makes sense (pro controller has a lot of stuff in it), while some of it doesn't (why two kinds of grips?). a subcategory here is 1 2 switch. if the noncharging grip was exhanged for thst, the switch would have a better value proposition at launch and thr grip would make more sense as merchandise, since it would serve a function and be a cheaper alternative to the pro controller.
the wii u had titles with more mass appeal. at least, on paper nsmbu is accessible and a nice multiplayer game. the problem was that nsmbu came out a few months earlier on a far more popular nintendo system. while botw is on two platforms, i can't imagine the same issue will plague the switch. botw is more of a spectacle and goes hand in hand with a system launch versus a system death. the wii u version will sell well, but the switch version will provide reason to get the system, especially since the wii u is no longer in stores.
following that, the wii u had a shit ten months. the wonderful 101, game and wario, new super luigi u, and pikmin 3 pale in comparison to splatoon 2, mario kart, and 3d mario. on the third party side, it looks like japan is going to be there. my assumption is that with dev kits only arriving in november, publishers can't commit to time frames. sonic mania is one of those games that clearly should be on the machine, but is happening late and separate of the other versions.
that's my feeling anyway. i am fairly positive about the switch and its chances, which wasn't true of the wii u a couple months before launch... or in the years after.