David,

You can also try a four-yard wool variety, rather than Poly-Viscose. I know a lot of guys on this forum swear by the stuff, but I've tried various non-woolen kilts in the past, and after wearing a traditional wool kilt, they just didn't do it for me. Your mileage may vary, but that was my opinion.

But you still have options. Your traditional kilt most likely has somewhere around 8 yards of cloth, making it a very spiff looking, but very heavy garment.

Let me suggest a four-yard kilt. Most of your major kilt making firms offer some variety of a four-yard kilt. The ones we offer through the Scottish Tartans Museum gift shop are Lochcarron's "Casual Kilts":
http://giftshop.scottishtartans.org/kiltpagecasual.html
These are essentially the same as your traditional kilt with two exceptions. First, the kilt is made from four and not eight yards of cloth, so the pleats are not as deep. Second, it is machine sewn, and not hand sewn, which is purely to keep the cost down so that Lochcarron can offer a lower-priced option.

Other firms will also have a four-yard option, though they may call it something different.

Your other option is to go with the traditional four-yard kilt, which is a box-pleated kilt (which I happen to make).
http://kilts.albanach.org/
These kilts are also four-yards, but are box pleated rather than knife pleated, and entirely hand sewn. This was the style of the very first tailored kilts of the late eighteenth and early nineteenth century. You can read more about the history, and the advantages of a four yard kilt, on my web site.

I recommend the 16 oz weight wool for a four-yard kilt, 13 oz is ok, but no lighter. You'll find that due to the reduced yardage, a four-yard kilt in even the heavy weight cloth is lighter and more comfortable than an eight-yard kilt in a light weight cloth.

And, of course, they are all entirely custom made to your measurements.

Aye,
Matt