You will get a very heavy and warm quilt with 2 layers of denim and batting, but it will wear like iron and be a great gift for anyone. I think you could do just about any type of quilting and have it look good, with the possible exceptions of flowers since it is for a guy. Straight lines will be ok, whether in crosshatching or just along the seams and would be easier since there will be many thicker seams to cross. Make sure you use a thread designed for denim, as it will be stronger.