Way back when, my first several quilts for my oldest kids were all large block quilts. The larger the blocks the better because that meant less sewing to get it done. I can imagine now what they looked like. I knew nothing of seam allowances except what I learned of the 5/8th in home ec. My kids all loved them. My kids ages range from early 40's to early 20's. My 24yr old son still has his block quilt; it's so warn out that only part of it exist and has to be kept in a plastic back because it deteriated. He still loves it and won't get rid of it. My daughter has recently started quilting and no matter what mistakes she makes I don't put her down, I encourage her and even for the few she's made and she could see her mistakes she's noticed two things, one, she's gotten better and 2nd, her friends don't see her mistakes. If you don't try you'll never get better. Do what you can now and let the kids love the quilts, sleep with them and enjoy them. In the mean time your skills will be better. Don't worry about the mistakes your going to make, 30 yr old quilters make them. Concentrate on the skills you'll build. It's a process to be enjoyed.