I do crawl under with a flashlight. I enjoy lying there under the table and looking up. It is so relaxing. I wish I had owned a longarm when I was younger, so I could have hidden from the kids under there, LOL.
There is a company that makes a system with a camera to let you see the bobbin stitches. I think it's called Quilter's Eye. There's also an Innova dealer who has published directions for making your own bobbin camera. The results are displayed on a monitor that can be attached to the longarm head or nearby. I haven't seen the need for this for myself, but I can see how it could be very useful.