Thanks for the feedback, I'm glad it worked out for you!
I debated whether to add an average column, but I ended up running out of room without going to ridiculously small margins or super-small boxes for data (or multiple sheets). As for the quality, I figure that's more of a personal definition. It would have been hard to describe multiple levels of finish quality without bringing in a bunch of instruments or tools that not everyone may have.
I probably didn't need so many circles and squares, but it gave me a chance to add multiple depths for more Z data points. I've also noticed that unless my machine is perfectly dialed in, small errors in small circles tend to be a lot more obvious than in larger ones.
I'm always working on the next version in my head, so let me know if you come up with any more comments or suggestions!