I had a non medicalised twin birth (so similar to VBAC in that I was high risk). I wrote a detailed birth plan and discussed it with my obstetrician who agreed and signed it so I could show it to anyone who said I was breaking the rules. I also had a long discussion with my midwives who added lots to my birth plan and got me to sign it too (no routine cannula, no continuous monitoring, etc).

I think as long as you make it very clear you are willing to do whatever if you deviate from normal most caregivers will be ok, but having your birth plan signed by your obstetrician may help. I completely understand the cannula thing though, I hate them in too and during labour I believe you need to be comfortable and not constantly annoyed by a tube in your hand which is there "just in case".

ETA one of my birth preferences was that no doctor came anywhere near me unless there was a complication, so maybe that's why he was so happy to let me have my way as he was in another ward having a cup of tea!