Blogging with an onscreen keyboard is painful, and carrying around tablet + bluetooth keyboard is more cumbersome than a 9" or 11" "ultrabook". The ability to run old binary-only windows/x86 programs comes in handy too.

What do you do for a phone? What works for me is: 6"+ phone that does anything I'd use a 7" tablet for (smartwatch means I don't need to take it out my pocket as often), 11" ultrabook for doing things on the go, 18" "desktop replacement"/"gaming laptop"/"luggable" for home and the occasional longer trip or LAN party. (I do have a desktop/"home server" but these days it's pretty much an oversized NAS).