Joel, as Ron comments, most people do in fact use their own bodies, and that seems fine. Personally I have never found the issue of ownership to loom large.
David, here are a couple of thoughts:
“Entertain” is an interesting word. It used to mean something like getting very involved with; now, in its more ordinary usage, it means something casual and not all that significant (“When I go to a movie, I just want to be entertained.”)
I appreciate your interest in bring space into the exercise from the outset, in the form of the space (context) in which the giant body appears. I realize from your careful investigation of this issue that despite the instructions, my approach to this exercise is ordinarily to leave the body alone and make myself very small, like Tinker Bell. Does this make a difference? I don’t know, but I’ll look into it.
Jack
Just a note to let people know that I accidentally deleted my question (about visualizing one’s own body) with Ron Purser’s response.
Joel