Kazuo Yoneyama, who was talking to hacks from Nintendo Online, said one the key features of the redesign is improving the machine's battery life, durability, reducing its size and weight.
Yoneyama said that the design was more than a matter of getting all the bits into the box as it was also important to look at the total weight and balance of the whole thing.
The team was also working off how to trade off a balance between functionality and size. In some cases this has meant ringing up the component makers and ordering some custom-designed parts.
This jacks up the price a bit so apparently the team have been trying to work out ways to avoid them. This has cost them a bit of sleep, Yoneyama said.
Although batteries on the prototype look the same, it has 20 per cent more storage capacity.
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