Okay, take this from an "older" beginning quilter with a grain of salt but I have become very adept at fixing my "creative errors" and I think you could square them up by re-sashing them with a similar color (blue at the top and cream at the bottom) like a narrow 1 inch for one suggestion; or by putting triangles in the corners to make them a less "wonky". Make pieced sashes in rectangles or triangles of similar colors from the panel to go on and then add a single lighter or darker color for the next sash. OR tip them at an angle on the quilt highlighting with larger triangles. Now remember, I have been quilting for only 1 1/2 years and I have been creative when I find errors in fabric. Hope maybe these ideas will help. Next time (don't ask me how I know this ;-) take a square in the fabric store and make sure the panels are square or ask the company online that you are ordering them from if they are square!!!! I have learned a lot over this past year and a half. Good luck!!!!