Really just function of mobility? Move a lot? 15-16 is combersome. Stationary often, maybe just roaming from your desk to your couch/bed? 16 is totally fine.

I'm in the 14-15 camp w/ lighter form factors being worth the premium.

I tried below 13 after the trend of smaller laptops from a couple years back - I now don't believe anyone who tells me they're regularly productive on these smaller form factors lol.