Oh good, do speak really honestly with your midwife.
I know that every labour is different but can I just say that I really 'enjoyed' my labours - maybe not every second of every actual contraction 
, but the overall experience was really exhilarating. And the post-natal tea and toast high is just awesome!
It's interesting what you are saying about 'setting yourself up for failure'. I think there's something in that for many people. There is such a fine line between having all the information and totally freaking yourself out tbh.
Because of that, I never had a birth plan because I decided I wanted to go with whatever felt right at the time.
I've known a number of women who thought they might want every drug known to medicine who had pretty drug-free births, and vice versa.
I thought I'd want to move around and be on all fours and push/deliver crouching down when actually with DS1 all I wanted was to lie flat on my back and get an epidural. My VBACs were totally different and I did not at any point want anything more than G+A.
Keep an open mind about how you are going to feel on the day.
Trust your body - chances are that it will know just fine what to do.
You want to be left alone in a dark room with DP and MW? Well, have you explored the option of a home birth??
Admittedly, I was very unbothered about the 'strangers in the room' (I just did not care), but I did always feel listened to, so don't expect to feel out of control and powerless. Have a good 'advocate' with you - your DP, your sister, a doula, your best friend: somebody who knows what you want and who is able to speak up for you when you cannot/are busy breathing.
I really hope you get the delivery you can look back on with amazement and pride, whether it's with or without drugs/whale music/epidurals/hypnotherapy/instrumental theatre delivery/scented candles.
Good luck 