I think they should keep the Wii U for 7-8 years like PS3/360. Keep it going a bit longer before the next system arrives, and try to recuperate their early losses, master HD development, and make their library as diverse as possible(also like the PS3/360).
The graphics/hardware push can't constantly be on the rev. It has to slow down and plateau at times(unless you love losing money) hence the 360 and PS3 going for so long. It would've been too damn expensive for either company to aim for the 5-6 year cycle. Also only AAA games/studios constantly demand more power but that segment has been shrinking. Nintendo and the others should open themselves up more to indie and mid-level games.
"Graphics is Power" - Nintendo Miyamoto.
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