First, congrats on making so many quilts. That's impressive! After all these years of quilting, I still have trouble with HST. They never seem to be straight on grain, are wonky and I ALWAYS have to ease in something when putting them together. Then my blocks usually measure smaller on one or two sides making the rows "funny."
One of the stupidest things I've done: My daughter got married in 1997. I made signature blocks and there were many wonderful, meaningful things written on the blocks. So I couldn't figure out how to trim them down properly, but I started cutting them down anyway. Many of them barely have seam allowances. Needless to say the blocks are now part of a UFO. Luckily my daughter has never asked about them. Perhaps I can finish by their 20th!