Irene - they are very easy to make and a lot of fun to do. You can search both Quilting Board and google for a lot of ideas for different variations of I Spy Quilts - and if you want to, PM me your email and I will send you some of my favorite links.
And my - you are ambitious - I had never heard of Patches of the Cross quilts, but they are a lot of cutting and, I assume, had piecing with all of the angles etc. I do spend a lot of time in Dr's offices, so handwork like that would be a good thing, but I usually take easy knitting projects that can be picked up and put down easily.
Post a picture of your quilt when you get finished with it!!