I have done a number of hand appliquéd wall hangings with my longarm. I'm computerized but if you take your time and use a short stitch length you should do fine with a domestic machine. Use a very fine 60 wt thread like Superiors Bottom Line or silk thread. If you match the zig zag thread as closely as possible in color you shouldn't notice the stitch in the ditch. Stitch as closely as possible to the zig zag. I'd try a sample first to see if you like it. I would not echo quilt. Use your creativity and do something grass like in the green, some clouds and something to indicate wind in the sky. Show us pictures of what you decided to do when you are finished.