fay, this is a beautiful quilt. and your FMQ is nice. One suggestion I would make if you aren't doing it, is to use the needle down feature if you have it on your machine, so that when you stop your fabric won't move or jump around. And most of all, remember to breathe!!!
I too sew for charity, and make about 150-200 a year. I think my free motion has improved by the charity quilting because I just go for it!