I made a pleated tartan skirt

[Pleater]

The reason for your skirt sitting low could be that it requires some sort of strengthening in the waist.
I use some really sturdy webbing materials at the waistline. After attaching the waistband to the outside of the kilt I fold it to the inside over the top of the webbing and secure it.
I make the kilt slightly larger than the required measurement and ease it in to fit onto the webbing as that takes the strain off the fabric of the kilt, which being wool would give over time and with wearing.

When working with lightweight fabrics I add a light weighting tape to the edge of the outer apron, the vertical edge, not the selvedge, sewn into the fold for about 6 inches up from the selvedge. It needs to be heavy enough to keep it down, but not so heavy it flies out or swings around too readily.

Anne the Pleater