"Do you stitch small projects one at a time that you can finish quickly, have numerous large projects going at once that you rotate, or both? How does your current system work for you and have you thought about changing it?"
First, I wanna say that's a great question and I'm always wondering that about every stitcher, so it'll be really interesting to read what everyone'll be saying on the subject.
OK, I hate having more than one project on the go. Why is that? First I like to sew and do other things besides stitching (and I also have a really demanding job), so if I had several cross-stitch projects and several sewing projects I would simply be tearing my hair. Second I tend to get nervous and insecure very easily - stitching or sewing is actually a way for me to keep serene... I'm always worrying about the future (i.e. what I can't control)... if I had several projects at the same time I know I would be actually worrying myself about not finishing them, or not knowing when I can finish them, etc.
This also explains why I'm quite shy in front of big projects. I tend to go for quick projects because I feel, "oh I can handle that, I know where I'm going". I have tackled some medium-to-large projects in the past... But though there are some large projects I'd love to stitch, I'm much more often inclined to start on small-to-medium ones...