The first point here is the reason I think the second might have merit and the rumor might be mostly false. If the Note were to remain one hand usable to the degree the current one is you would need a different device for the bigger size.
If you add a size though I think you goto 7" or so and drop the ear speaker in favor of headset or speakerphone use only to save on overall size and pocketability. 6.3" will be too big for one handed use and a bit silly looking up next to the noggin also, but not really into a size realm that really starts to change current pocket options the current Note's fit. I think you may as well goto 7" near bezelless if this pocket size thing is the biggest driver.