Here are some of the features of the kungsleden trail itself

The boardwalks are often over bogs or streams, sometimes over washed out trial, sometimes just there to make walking easier

I went 4 km on the wrong trail because someone decided different trails did not need different color blazes.   The wrong trail I followed was blazed red, just like the kungsleden.   I got to a junction with two red blazed trails and followed the wrong one.   There was no sign at the junction saying “kungsleden”.   Fail.   I wound up backtracking 1km and navigating 2 or 3 km across open fell to get back to the trail.  The clue was that the trail was seeming less traveled, then I got our my detailed maps and GPS and figured out how to get back on track without a full 4k backtrack.

Not seen on the entire trail: switchbacks, water control features such as check dams,  rolling grade dips or anything to divert water off the trail.   Often the trail went straight up and down hills.  The New England Appalachian trail designers would certainly approve !

To be fair, this is a different kind of trail that is completely covered in snow 7 or 8 months of the year, so different methods may be appropriate.