Satoru Iwata himself said ones that the only reason what held back Nintendo Wii U was not the price, it was the less 3rd party support! And I agree with him, if people want something really bad than the price doesen't matter! Kid buy today 600 Dollar Smartphones or 500 Dollar Tablets, if they really want it they buy it. And thats the reason why Nintendo really should release a more powerfull console for 400 or even 500 Dollar. If it's a cool console with alot of power than people will buy it also for 1000 Dollar ;)
Wrong. You are totally wrong if you think that less 3rd party support is only thing that held back Wii U, Wii U was bloody mess, and high price compared to competition is definitely one of reasons why Wii U failed. You need to realise when Wii U launched had similar power like PS3/Xbox360, played exactly same multiplatform games without almost any difference (actually some 3rd party games worked and looked worse on Wii U) while had around $100 higher price point than PS3/Xbox360, even now Wii U is just $50 less expensive than PS4/XB1, and thats just crazy. Also Miyamoto stated that Wii U had higher price than they wanted.
Nintendo needs to release console that have similar price point like competition, if they have better hardware or they offer some cool new feature they could price it little above ($50), but point is they need to have similar price like competition if they offering similar things.
Saying that, Nintendo can release NX at end of 2016. with hardware little stronger than PS4 and to have price of $299, and $299 price point for console is magic price.