YABVU, OP. Mine was ignored by the MW with my first birth, but was just the NHS one that came in the notes (by ignored, I mean being injected with painkillers without my consent, having the injection for the third stage without consent, having a head monitor on DD without consent, and still not knowing to this day if I had a tear or an episiotomy as both things are on the notes in contradictory fashion. Ignored.)
So for the second and third, I started discussing birth "options" (in fact, telling them what was going to happen) at booking in. My birth plan was written with the MW who delivered DS1, and with DS2 the one I saw for every appointment (but who missed the birth because she was on holiday - however, her replacement was equally fab.)
It was followed to the letter. No decisions were made without my input, and I went against hospital protocol with the full support of my MW, because she was able to read the birth plan, talk to me and realise that I did know what I was talking about.
I would not "go with the flow" if going with the flow means conforming to over medicalised hospital policy, that is what led to DD being in distress and me having a horribly traumatic time first time around. A prescriptive birth plan and masses of communication between me and my care givers enabled me to have good births, and I'm glad of it - but it would be totally impossible in a hospital setting.
If you don't like prescriptive birth plans, don't have one, but try to understand that people who do often have very good reasons for doing so.