CenteringPregnancy at Kaiser Oakland
I'm with Kaiser Oakland, with Dr. Sarah Wilson as my OB. She is fantastic and I highly recommend her. I also did the prenatal group program during my pregnancy (my son is now 1 year old), which I believe has evolved into the "Centering Pregnancy" program as you've described, and I would highly recommend that as well. We ended up choosing one of the Family Medicine doctors who led our group as our son's pediatrician. We still keep in touch with the other couples who were in our same group, and have become good friends with one couple and their baby in particular.
I can't speak to the "holistic" approach as you've described, but I will say that Kaiser did very few ultrasounds during my pregnancy. I think I may have gotten one per trimester. Otherwise, they just used a doppler to listen to the baby's heartbeat at the checkups.
As for a water birth, I doubt that the Kaiser Oakland hospital facility could support that. Another couple in our Kaiser prenatal group did a home birth with a water birth, however. Kaiser Oakland hospital has all the drugs, including nitrous oxide, for pain relief during labor, but I've heard of plenty of women who did not opt to use any when giving birth at Kaiser. The Labor & Delivery rooms at Kaiser Oakland are spacious (so there's lots of room to walk around, use a yoga ball, etc.), and they come with a shower. Kaiser Oakland L&D is also run by midwives - a midwife on duty supervises the OB residents, who take care of the laboring mothers. All the residents that we interacted with during our stay were excellent.
Also, my understanding is that you can also opt to give birth at Kaiser Walnut Creek, where it's all midwives (no OB residents).
I can only speak to the Centering Pregnancy option...and this is just my own experience.
I wasn't sure about it and we went to the first two sessions and ultimately decided it wasn't for us. This was simply because we have a lot of outside resources (a doula, a prenatal psychotherapist, I have been reading books since early on, hypnobirthing classes, etc.) and it felt like a lot of time to invest to be learning the same things we already knew. What we were hoping for was to connect with other new parents and maybe form relationships outside of the group but the particular group we were in didn't seem interested in community building (though maybe we jumped shipped too soon). I would say try it and thankfully they give you the option of going back to your previous OB/Gyn. When you do the CP program the two doctors who run it (and you don't get to choose I don't think) become your OB/Gyn for your pregnancy and the group meetings take the place of your other checkups so that's something for you consider.
Hope this was helpful. Happy to answer other questions if you have them.