Unless Apple engineers know something that Intel, Nvidia, and all other chip manufacturers don't know, they cannot shrink the MBP, make it more powerful, and make it run cooler all at the same time. At least, no more quickly than those component makers can.
There is a balance between thinner, low-weight and power. A computer, laptop or desktop, is a tool - its usefulness is judged by how good of a tool it is.
Nobody has yet to make the case that the current MBP is too heavy or unwieldy to be truly portable. Yet this forum is full of people who ask for more power and functionality from their MBPs.
Apple must fill the requirement gap. For those people who put a priority on weight and size, there is already an offering. For those of us who need a desktop substitute we absolutely, positively do not need for this laptop to be any smaller as long as those other needs are outstanding.
If you're willing to shave battery life and power out of a MBP in order to have it be a few mm thinner, I really question why you're in a MBP forum.