A krait cpu will be more better, 1-2gb ram, use a universal micro usb, hdmi,wifi b/g/n, 7 inch hd disp,and do the back casing with brushed aluminum ( can use the body to conduct heat out of cpu,gpu,memory,and power chips) , 4000+ma 7.5 battery ( advantage of powering the usb/micro usb port directly with out boosting circuits), 2-4 gb high speed samsung nand memory and micro sd card and full size usb i/o port.
Software :-
Use unlocked boot loader, arm chips are the best suited ones which supports almost all mobile os( win,android,Ubuntu etc). Keep the hardware a future proof and give out proper sources. Use unrooted os, let it be the first tab to support any os a developer want to try.
Regards
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