I connect 16" under a big display but I find that I look at the 16" as main and dislike turning my head to look at monitors. My conclusion is that only a 24" is practical or any single screen while sing spaces since I get tired looking around to read off screens. I want to say that 16" is ideal for around the house use but a joke if you travel on airplanes and want to use it there.
I did use a 15" for 6 months travel 100% of the time. different hotel every 3 days and it was ok to use.
I want to say that ideally you need 2 laptops. 16" for home/office use and a 12" for on the go and airplanes. I tested both for travel over 3 years and the 12" was a must for on the go. 16 is nice to have at home. Big screens are not really all that practical for general use. too much looking around to find things on screen. My brain wants to look straight. 14" felt kinda small to me compared to the bigger one at the store.
What about 14" for travel and at home using it only in clamshell mode with a big monitor though? Then you don't have the "looking around" issue and just a nice big 30" or so screen in front of you. Avoid buying a second laptop, but of course adds a monitor ($500-$1200), keyboard with touchID ($150), and wireless mouse.