I think it is a lovely quilt, although not very simple. I suspect that you have some irregularity with your seam widths, causing the problems that bothered you. For a new quilter, its a good idea to recheck your seam widths as you go along so you can fix them easily and avoid problems with subsequent steps, not that there is anything wrong with the way your flimsy looks. I tend to trim/check blocks before I sew them together as well.
don't put yourself down. You did an excellent job.