Thank you for the words of advice. It sounds like it's just a matter of practice, practice, practice! This is not a quilt that I'm overly sensitive about and the oopsies are really minor so I plan to keep going. I am learning a lot and getting loads of practice. I DID use several quilt sandwiches first, but they are much easier to work on and did not give me the full experience of working on a large quilt...moving the weight around, having it pool in my lap, catching on things... There are some things that I could only learn working with the real thing!
Most of the quilt is light colors where my light colored thread doesn't not stand out but here is an example to show what I mean. This square shows a couple spots that didn't transition well. One is at the lower left side.