Kind of like how they should have supported the GBA for a full 5 years because there was a shit load more money to be made from the GBA than the Wii U could ever dream of. 

Yet they replaced it (effectively) with the DS. 

Was that the wrong decision? 

For me personally as a gamer honestly I don't give a fuck. I have to buy an NX at some point, doesn't matter if it launches tomorrow or in 2020, I like playing Nintendo games, so for me it doesn't matter if I upgrade this year or three years from now. There's no difference. There's $300-ish in my bank account with NX's name from the moment it was a twinkle in Mr. Iwata's eye. 

There is no "oooh, maybe I'll buy it, maybe I won't" dillemma for me, so that frees me up to look at it from a cold, purely market driven side.

If you asked most Nintendo fans in 2003 should they replace the GBA soon, I gauruntee you most would have voted "no". 

But that rationale is not based on any market logic, it's just personal preference. You may think the Wii U is just fine and dandy (and I just for the record have a lot of fun playing mine), but I can also gauruntee you there isn't a higher up on Nintendo's board of directors that's happy with how the Wii U has done. 

Wow, didn't know software sales were that great for Nintendo consoles comparitively. Impressive.

they did support the GBA for a full five years. in fact, they released the micro in 2005, almost a full year after the DS launched. regardless, handhelds and consoles are different. consoles today are much bigger investments than handhelds in the early 2000s. 

hahhaa, i have a similar mindset when it comes to buying nintendo products :P ;)

But the DS was a gamechanger that was fully realized and had a lot of great games at launch in a time where it didn't take years and millions of dollars to make games. Now more than ever the reveal to release has to be perfect. 

yep, thats right! but remember, nintendo is irrelevant.

If they've been cutting Wii U projects short to transfer them to the NX, they launch window is something I'm not that worried about. 

Zelda could be in the launch window and EAD Tokyo's next 3D Mario is due around that time too. Animal Crossing would be due in the post launch period. 

Also remember Nintendo would only have to support one platform in a unified structure. That means game development wouldn't be split between two systems, which is a core problem for Nintendo. 

If it's a powerful portable it likely will see a shit-ton of third party support early too (especially Japanese devs) so Nintendo doesn't have to work so damn hard either. You're not supposed to have to sell a game platform all on your own, it's not supposed to be like that. For third parties it's better to be out sooner so you can start building that all important user base, the sooner you get past that 10 million barrier the better. 

And actually the DS launch was kind of ... shit. It picked up in 2005 and found its legs with Brain Training in Japan but really took until 2006 in North America and Europe with the release of the DS Lite to really put up big sales. Before that the PSP would outsell it fairly regularily in the West. But had they waited it would have been disastrous because it would have given the PSP too much traction in the market, so Nintendo was 100% right to launch the DS in 2004. 

The other thing that really killed the Wii U and 3DS launches is Nintendo banked hard on casuals being there. NSMBU *should* have been a killer app, the previous one sold a bloody 30 million copies or something. Nintendo Land should have been a huge hit with the Wii Sports/Mario Party crowd. Nintendogs + cats *should* have been a killer app for the 3DS launch, the previous one sold 30 million copies too or whatever. Nintendo got stood up by that casual audience, they won't make that same mistake with the NX launch window, I'd expect Zelda with Mario not too far after that and Splatoon 2 early in the cycle for good measure. 

Metroid Prime Hunters: First Hunt demo, Animal Crossing, Mario 64 port, and Mario Kart were all "launch titles" (within first year). Not really all that terrible.

EAD Group 1: but you have to take into consideration that Mario Kart games NEVER Launch with the console, and, since they need a 3 year development for a MK game they could release it by the end of the 1st year of NX/during the 2nd year .

EAD Group 2: both Splatoon and AC:Amiibo festival didn't need many developers and development for both (counting a few months after release for the additional weapons in Splatoon + additional bug fixes)  ended probably in July/August 2015 leaving pleanty of timeto make other games/working on the new console interface;

EAD Group 4: Again, team that is confirmed to be split due to Pikmin+SMM, I think the development of the latter might be one of those who took the lesser ammount of developers in Nintendo's recent history, Pikmin HAS TO BE an NX title, if it is a Wii U title it'd be in Nintendo's interest to keep it a secret so that they can surprise us at E3, instead Miyamoto threw it out there as if it was nothing;

EAD Tokyo: since Captain Toad used the same engine as SM3DW it's likely too that most devs started working on the next Mario game right back in 2013...

Retro: There's something called moving projects to other platform, it's what happened with Star Fox Zero that was originally a tech demo for the Wii, also I wouldn't be so shure about the dev kits assignements inside Nintendo...

HAL: Imho they have had somethinkg big under the curtains since they've been releasing simil-minigames lately

Intelligent: Translations are made b other companies, development ended in March 2015 or a few months after that considering DLC, still they might be able to publish something by the end of 2016/early 2017

ND Cube: as you said, they could release something by the end of the year EASILY

Monolith: Their development cycle doesn't count since they release games after 4/5 years :v

What indicates to me that NX arrives this year.

- New unified account system which falls in line with speculation NX is a unified platform.

- The fact NX will be unveiled this year, I don't see Nintendo trying to keep everything about NX secret only to unveil it then wait a year and a half to release it allowing their competitors to prepare for it. As someone mentioned earlier the days when something was reveal then released over a year later are gone.

- 2017 will be a harder year to launch in then 2016 as the other platforms enter their stride.

- Wii U as it stands has no 2017 projects and this year's releases are projects that were delayed or announced in 2014 indicating resources were diverted to NX.

- Zelda U's delay draws similarities to TP's.

- NX is part of Nintendo's new approach, the new approach consists of extended businesses in licensing characters for movies, animations, theme parks as well as entering the mobile market and the possibility of starting a chain of stores like Nintendo World. The will even be a reward program that spans across everything for consumers, all of this comes into play this year so why would the NX which is part of the approach launch next year.

I'm not talking about forcing. Sony isn't better at selling hardware, it's the 3rd party games (with most of the generations the games being only on ps) that sell hardware. Try imagining how different things would have been if the ps, ps2, ps3 and ps4 exclusive 3rd games were multiplat/ full multiplat.