I thought 15.0* to 15.4** might be more likely based on the perception - Apple could then have the 16” still be ‘bigger and better’ in people’s minds. You could then also have the Air line at 13 and 15 inch with the Pro line at 14 and 16 inch, but really either way would be good for me

I’d also be very happy to see a 17” Mac laptop of any sort return to the lineup, though I can imagine the price would be astronomical if it sits above the 16”!
* same as the surface laptop 15
** same as the previous MBP