I bought a Macbook vertical dock so that I close my laptop and connect it to two monitors, a keyboard, and a tablet and effectively use it like a desktop.

That basically solves 1, 2, 4.

3 doesn't bother me because I have my headphones on most of the time. If I'm at my workstation, I use my speakers.

5 is subjective. I've been able to get around for the last year as an on-the-go freelancer without much problem with the size or weight.

This allows me the huge advantage of mobility (for working at difference offices, cafes, houses, travelling to other cities, or even different rooms in my apartment) and space savings (I can have my vertical laptop on my desk which takes up the same amount of space as a small lamp) to be coupled with the advantages of having a full-fledge desktop setup.

FWIW, I spend most of my time using graphics programs.