Welcome to the batiks!! I love them too. I got some from connecting threads also and I really like them. I believe that they should be 100% cotton. and yes you can mix and match them with other fabrics and prints. I have before. it just depends on the batiks. they will speak to you and tell you what they want to be. just keep looking around for patterns. quilters cache and many different quilters websites have free patterns for blocks and entire quilts. it is kinda up to you what you do. and as long as you listen to your fabric you can't go wrong. if you post a pic of your fabrics it will also help people point you to a pattern or block.