WiiU was Nintendo's Sega Saturn. They're gonna have to pull something amazing out of their ass for NX.
No it wasn't. First off, the Sega Saturn did really well, just not here in the US. Secondly, Sega didn't have a best selling handheld making them money hand over fist during the Saturn years. Lastly, the Wii U wasn't the third flopped console in a series of flopped consoles.... the Wii sold fantastically and the Gamecube sold respectively well. I get it, you aren't fond of Nintendo anymore, but you aren't making objective comparisons.
I do agree that they need to do something, but the reason is the new President of Nintendo isn't a gaming insider. If they don't make money on consoles he'll most likely cut the console division. He doesn't understand that while consoles sometimes make them lose money, it keeps the IPs alive, so they HAVE to do it.
According to polls at least, you are in the minority. Most Nintendo gamers, particularly the Japanese ones, want physical media. I doubt Nintendo will ever do a unified shop like Sony, because, unlike Sony, their old games hold their value. Why would they let you buy Zelda once when they can make you buy it every console generation? It sucks, but it's good business. What I think they will do is start releasing compilations. The NES Classic seems like a test to me. Hardware costs aside, you are getting those games for 2 bucks a piece, which is considerably less than their VC counterparts. The more than one device thing is NEVER going to happen as it weakens the brand. If you could play their games on, let's say, a cell phone, they would no longer have a strangle hold on you to buy the next console. Also that's the scary part of this whole thing. When the NX launches, they will have one, and only one console. 3DS sales have finally started to drop and yet they haven't announced a new handheld... the NX IS the new handheld AND the new console, so if it doesn't sell well they are screwed.