I have not delivered at U of M, but saw Kathy until late in one of my pregnancies. I really liked her, she viewed pregnancy as normal and the prenatals were laidback. Ultimately I switched only because when I started asking 'what if' questions about potential complications in labor, she didn't have a lot of answers and seemed to be saying I would be handed over to a resident without much decision making by her. I wanted to hear more about how issues are typically handled before actually being in labor.
That was a few years ago, though, so maybe the midwives have more autonomy now? I would ask.
I do have several friends who have had good natural midwife births there. They mention that the hospital policies on monitoring, i.v.s, cervical checks, etc are fairly restrictive and perhaps a bit repetitive as students are learning, as is typical in any teaching hospital setting, so it might be wise to clarify with Kathy (and your doula) exactly what you are hoping for. It is a midwife but not necessarily a 'birth center'. I hear the new Womens Center is nice and does allow waterbirth if the one tub is available.
I'm so glad you feel comfortable there. That is the most important thing. I hope you get some input from someone who has personally delivered there!