Never be put off by lighter weight fabric. In my opinion it is absolutely necessary to work with this stuff to get the skills to make kilts. Besides, you can put in a liner to add body to the aprons and to make up for any "thinness". I have done this many times with good results. The kilt's end up being light true, (not necessarily a bad thing in the summer) but of good body and feel. No they are not tanks and never will be, but I think there are room for kilts of all fabric ranges. If the end result is a good looking and good feeling kilt that gives the owner some sewing practice, then why not?

For someone who is just learning I think it's a bit much to ask that they start with $80 a yard 16 oz wool unless they are being mentored by someone who knows what they are doing (like one of these kilt workshops). It's pretty intimidating for a beginner to cut that stuff because it is a huge investment.

Good on ya, for trying this. With the lighter weight, cheaper fabric you won't be afraid to try things, and that's where kilt making skills (learned on your own, with just the aid of a book) come from.
Jim