I don't think you're going to see a big enough difference between the two to deem one more comfortable. Although I don't have a 16 inch, I had a 2015 15 inch and went with the 14 inch this time around. Surprisingly, I actually enjoy the new keyboard more than I did the old one and it's more pleasant to type on generally speaking.
The surface area that you can rest your wrists on is larger on the 16 for sure, but in reality - how much of your wrist ACTUALLY wrests on that area when you're typing.