Focus on the 70% that sounds like you have a really high chance of succeeding. Its kind of invasive when everyone thinks they know your body better than you do.
I was determined to have a VBAC with my second after an EmCS with my first. I went over, I had two sweeps - one on due date and one a week later, a failure to proceed labour, a very fed up family (can't you get on with it) then ended up with another CS as they wouldn't let me hang on any longer. On the one hand the birth was wonderful, stress free and my DS latched straight on in the recovery room. I wasn't tired, it was mid morning so I had the day to enjoy him and for family to pop in.
On the other I wish I'd thought it all through a bit more and not felt so disappointed at the time. It overshadowed things a bit for me - I sort of felt like a failure even though it was just one of those things. It was definitely best he was born once I was two weeks over.
I think that after the trauma and exhaustion of an emergency procedure I was keen to have a less traumatic birth - with reflection I got that with no.2 even though it was a CS.
Now I'm in early days with no.3 and having the same discussions with a new set of midwifes in a new area - its just I have two scars this time!
Its your body and your choices have you got an action plan to get things started? All the traditional things, long walks, hot currys, rasberry leaf tea (yuck), when you can have a sweep and who does it in your area.
Finally if after you've tried all else would you consider induction at 41weeks over waiting to be two weeks over and not being given the choice? Its just if you get to 41 weeks and you haven't previously indicated you'd like to try induction they may not be able to fit you in which would be seriously frustrating.
Good luck and don't let them get you down.