I don't know about Vegas and Delicious but Adora to my experience is relatively a conservative dancer to PM's standard. She has always taken me to the middle one on the right. I can't really understand how it could be most private as being in the middle sandwitched between two other CRs without any walls or barriers and can be seen by another three CRs on the opposite not to mention walking dancers/patrons who may be going to the back CRs during the dance but that is just me. I prefer the back CRs.
No question, the three 'back wall booths' are by far the most private in the 'Mate's CR - no doubt about it. It also may be true that Adora is a relatively conservative dancer by "PM's standard".
I certainly did not mean to imply either that Adora is or is not "conservative" or that her preferred booth is in any way the "most private" as zbla suggests she may consider it to be, but only that the three dancers mentioned seem to "have their favourites".
On the question of privacy and conservatism, Vegas seems to prefer a 'side booth' (to the left) and while I've not experienced the full range of conservatism and liberality at the 'Mate, I'd be surprised if many would consider her to be at the conservative end of the spectrum. This is only one dancer's apparent preference, however. I suspect most of the less conservative ladies favour the 'back wall booths', as you suggest, H_K.
Having said all this, I'd note that patrons entering or exiting the 'last' of the side booths (i.e. those 'side booths' nearest to the back wall) may have a fairly open vantage point to observe activity in the 'back wall booths'. I try to avoid this out of respect for the privacy of both patrons and dancers. Recently, while Delicious was waiting for her preferred booth to be vacated, it was difficult not to notice (at least momentarily) Ashley in her preferred placement. Apologies to Ashley and to her patron, but I had the impression he was oblivious to anything except Ashley's 'attentions'.
There was a time when the 'back booth' chairs had very high backs, and this afforded quite a bit of privacy, but that was some time ago.