There are some links to very good cloth sim information such as the Maya Cloth manual, on this page. Copy and paste link into browser as I haven't gotten the hang of direct links  here yet.

http://www.poserfashion.net/About%20cloth%20simulation.htm

The information is not Blender specific but the concepts are transferable to Blender and will give you a good basis for improved cloth simulation.

A couple of the links on the page are to white papers so aren't necessary to read unless you want to know more about the mathematics behind cloth simulation.

I get good results with  this method in situations like you described:

Add a circle, scaling to the circumference of the waistband
ALT+RMB>E>ENTER>ENTER>S  to scale out in a planar direction for creation of the outer circle (the hem edge) Do not move the mouse during the extrusion part of the preceding sequence. Ideally select the circle then take your hand off the mouse until you reach the scaling step.

Select one of the radial edges then CTRL E>loopcut  using the middle mouse button to increase the number of loopcuts to the desired amount. Just try to make a reasonably evenly divided layout at this point. Arrange for any longer or shorter areas or splits on the finished garment. (angled skirt, split skirt, etc.)

(Here's where you get to use the irregularity of poly reduction to good effect for a change.)

First subdivide the mesh to the highest level your computer can handle.

Use either the decimate modifier or the poly reduction script to bring the poly count back down to a reasonable level. This randomizes the poly layout within the boundaries which for the purpose of a cloth sim is a GOOD thing.

Convert quads to triangles and UV map using project from view for an undistorted circular map.

Run the cloth simulation.

Alternatively you can create the skirt using the above method on two mapped planes (rather than an extruded circle) that are UV mapped then joined before running the cloth sim. This allows for better texture creation of patterned fabrics.