I kind of agree with you that I'd like to see a small laptop with a larger screen (still 16:9 widescreen ratio) and a good size keyboard without trackpad, in the new 'touch' world. Get rid of the trackpad that compresses the keyboard space and offers dubious
utility.
But like the last response, I don't see that as very reasonable in a 'tablet' formfactor. and any keyboard still needs a little bit of 'palm landing area' to be comfortable to use longer term, so I'm not sure how much space one would really gain.
The Surface Pro is about as big a 'tablet' I think it would be comfortable to use, at least until battery technology (or low-power processor and hardware demand) lets things get much thinner and lighter. Then something in the range of the size of a piece
of standard 8.5 x 11 inch paper (or worst case, the size of a typical clipboard holding a piece of paper) in portrait mode might work as a tablet.
EDIT - just read about the Acer Aspire R7. Might supply the formfactor you're after. 15ish inch widescreen, touchpad *above* the keyboard, but the screen hinges and 'swings' forward at the base to hide it, and it can also flip around behind (flat) for
tablet like formfactor.