This may just be my loopy self, but how about the power button?You're comparing an iPad to a video game system. What people want out of each of them isn't going to be the same. It's apples and oranges.
And you're missing something big; it's not just about whether it can fit in people's pockets or not. Without a seamless sleep mode like the 3DS, it won't be very good as a handheld whether it can fit in pockets or not. Even iPads you can just lock and put away at a moment's notice if need be. We haven't seen if the Switch can do that. That's far more important than its size. Any portable device needs to be something you can start and stop using at the drop of a hat. Until the Switch has that, it will never be equal to the 3DS in terms of portability.