I quit doing SITD because it made me too tense. It takes constant concentration, not to mention being very slow. I agree that using a fine thread (such as Bottom Line) would makes straying less noticeable. What I opt for instead are just lines -- either straight or wavy -- and a walking foot. When the line doesn't have to be right in the ditch, it's easier to sew.
Here are some images of straight line quilting with a walking foot, without regard for SITD:
https://images.search.yahoo.com/sear...demail_chr_win
And here are some images of wavy line quilting with a walking foot:
https://images.search.yahoo.com/sear...F-8&n=60&x=wrt
Both are much easier than SITD and far more relaxing.