Should be fine, as long as it feels like it "hangs" right.
My last kilt - a four yard box pleat - is an 11oz poly rayon blend, which feels great, holds pleats, and has a wonderful "swish"

If you're not that experienced with sewing, and you have enough scrap material, try some basic mock ups on smaller pieces before moving on to wrestling the full piece of fabric - sew down some pleats on a small piece of tartan, etc.
I know it helped me.

Also, do you have, or have access to a kilt you can study in person?