I've used the PSP Go and Xperia Play both of which have a similar setup and had no problems other than that they were probably a bit too small.

I like this type of design too, where the screen slides up and tilts up. 

torque =  r x F = r * (ma) * sinθ

ipad air verses pspgo.

469g / 158g = 2.968  is the factor by how much larger r is in evaluating torque.

169.5 mm (depth, height is 240) / 69 mm = 2.456 is the factor by how much larger m is in evaluating torque.

...so without doing an integral analysis the torque is about 7.29 times larger.   aka, hugely more torque.

There's lots of slider tablets too. I don't think this would have a screen the same size as an iPad mini though ... 5-6 inches max I think. Still a good size for gaming, but a smaller screen keeps the cost down. 

Maybe one like this? You can play without the physical buttons if you don't desire them. It can be seen like an add on, but it's included with the Nintendo's Galaxy esque design for $199.99.

That looks much better, but without the removable part.  The buttons and sliders should just be a part of it, and the screen larger with no wasted space.  Sleek, but able to play games with proper controls.

I proposed something similar in another thread, I really like the idea of a Nintendo tablet. It should be compatible with the Wii U so it gives Nintendo the option of removing the tablet controller and make it optional, lowering the cost.

The tablet has to be good but cheap, less than $200 would be fantastic. But the most important thing are the games, one should have immediate access to the Virtual Console at least, and with a proper account system to be able to play them on the tablet, Wii, 3DS etc.

Without an account system then forget it, that thing would fail for sure.

It's an interesting idea, but I'll eat my hat if it ever happens.