What's the point to disable keyboard when using the mouse? really, 2 headphone outputs? Why is a better option to have a gravity sensor on screen in a one piece device? I'm a bit confused
the keyboard switch is for enable/disable the keyboard. if you're playing with gamepad, most probably you want to disable the keyboard for avoiding accidental keystrokes (as example, pressing power button, esc, etc)
then a switch that simply enable or disable the keyboard will be so useful.
(is not the mouse switch)
2 phone outputs, yes. Is not uncommon, there are lot of devices with two outputs (JXD, Yinlips, etc)
the main goal is plug your headphone on the front , to avoiding accidental messing on the back.
now, i'm thinking that the back headphone is not necesary, because if you want to plug the device to get external audio (tv, etc), you will use the HDMI output instead a headphone output, then my suggestion become to move the headphone plug to the front.
and gravity sensor on the screen, is a must have in my opinion.
if you're playing with the deice on your hands and move it, depend on the horizontal level may the screen change their orientation, but for you is most natural that the screen itself have the right orientation.
this is a behavior that many users that paly on their GPD-XD experiment. Sometimes you're playing and the screen orientation changes, and many times you take the screen and move it trying to get the right orientation.
For this reason i consider that the orientation sensor must be on the screen part of the device.