I used to do simple jackets using denim and corduroy, all cut into squares and put together checkerboard style. I did not like the way they worked out onto a sweatshirt, so I cut the pieces from my patchwork as though it were regular fabric. I made the patchwork with my serger so the seams would not ravel, and some of the seaming also. I thought they worked out okay, and I used bits of lace, buttons, and other trims to add a little sparkle. Needless to say, my daughter's jackets were not like anyone else's, and they were pretty easy to find if she left them at school somewhere. I think using your denim and batiks will work well. You might want to make sure all the seams are pressed toward the denim to ease the thickness of your seams. Good luck!!