A depth and reveal that equal will work if the depth is 3.5" and the reveal is 3.5"... but it will look silly. Those are some WIDE pleats brother!

For a kilt (if the tartan repeat is workable) is to work around a 3-3.5" depth to a 3/4" reveal. That's not "always" possible since some tartan patterns are smaller or larger. You'll see what I mean as you go and check-out more material.

As a rule of thumb, try to make the depth around the depth of your pointer finger. It's not an exact thing, but it's a nice/easy way to see the "workability" of the pattern.

As for the weight of the wool... both make great kilts. The thicker will take more time and a different method of pressing to get it to stay with knife pleats, but it's a finished product that's superior in strength and look. The sway will also be enhanced with the actual material weight in the pleats.

Just try to find a "tight" weave that won't allow stains to penetrate the material as easily. That's only a problem if you're looking to wear the kilt at Pubs and outdoor events really.

~If you're going to stick with the 4-yard (approximate) kilt, you'll need to adjust the pleats to a wider reveal, and possibly consider making it "to the stripe" in order to get some depth. It's normal for a casual, and CAN still look pretty sharp if the stripes are vibrant. It will draw the eye to the stripe configuration, and pull it away from the actual number of pleats.