I have a friend and customer here in Victoria who lives in the Great Kilt as part of what this thread has dubbed "Experimental Archeology".
He uses a piece of cloth of the weight of an army blanket because that is about what a hand loom of the age would and did produce. (His wife wove it)
The length is about 4.25 yards and length 54" as it is two pieces sewn together. The length and width are perfect for rolling up in at night as a sleeping bag.

He wears the Leine constantly. (He washes his about every 3rd day but in the Highlands it would have been washed about once every other week or so.) His Leine is hand woven of Wool and about the thickness of a Pendleton Wool shirt.
The other clothing he uses are a pair of "Ghillie" shoes. Basically three layers of Elk hide for a sole and laced up the calf. In cold weather he adds leggings of rabbit fur, fur side in, laced with the shoelaces.
A long leather belt with no buckle. Instead it uses a horn toggle.
A large shoulder/belt pouch to carry everything he owns when in the field.
A large bladed knife in a belt/shoulder strap.

In the morning there are all sorts of things that need attending to like stoking the fire for breakfast, fetching some water, and his ablutions.
His method of getting dressed is this;

Roll out of the blanket and wrap it around his shoulders.
Go Stoke the fire.
Find the latrine and relieve himself.
Fill a water skin and splash water on his face, hands, feet, pits, and crotch. Dry off with the blanket.

Go back to the camp and put the breakfast on the fire.

Finally, standing in front of the fire to get warm he pulls the blanket over his head and shrugs it around his shoulders.
He then grabs his belt and flips it around his waist and fastens it in place catching the blanket in the process.

Voila, he is dressed.

He does it standing and it takes all of a minute to do.
To get the sort of effect and imaging what it looks like find a picture of a ladies Arasaid. Same sort of look.
It's a Leine and Brat sort of look.

After he is warm he drops the top of the blanket off his head and pins it in front with a pennanular brooch. Over both shoulders and Pinned a little to one side so it won't get caught when he slings his pouch over his shoulder before going out to tend the sheep or chop some wood.

Does it give the look of those in the portraits? No, I'm sorry it doesn't, but it works very well, is practical, and simple.

I think we tend to forget that hand woven fabric are far thicker and heavier than those we use today. To me the army blanket weight is exactly what I would want around me in the damp Scottish Highlands.