When I was pregnant with DD I had the same feeling about one of the MWs. I always said to myself, "Anybody but her!" And I wasn't the only one who felt that way, two other friends who went to that practice said the same thing. There were 8 MWs so I figured the odds were in my favor. Wouldn't you know it, the day I went into labor it was her. Their shifts are 24hours and she was two hours into her shift, so I knew it would be her.
It was a busy day in L & D and I didn't see much of her. She came once in triage and the other two times were at my request, first to be checked and then to start pushing. She was actually great through pushing and stitching me back up. I think more important is your L & D nurse, because that is the person you will see the most.
As far as things you can do, I think the only thing you can do is labor at home as long as possible. Good luck and hopefully if you do get her your experience will be similar to mine. Oh and now when I see her I look forward to it. She still remembers DD's birth two years later and I feel a connection to her because she caught my daughter, so keep an open mind she might surprise you.