First, welcome aboard. Second, look under General Boards for  "FAQ for newbies" which will help you alot. Next, use the search function under the reviews section.
Good luck!

The attributes you are looking for in a provider are vague, it is hard to pin point an exact provider for you but the MN Top 100 is a good starting point.

Remember in this business, young starts at 30. You might find providers that advertise their age as 20's but their real age is 30+.

Given your preferences Whitney Cohen, Bianca James, Wendy Martin and Sweet April come to mind.

If you are a P411 member you might find a couple more on there that don't yet qualify for the Top 100 criteria.

You might also want to visit the Newbie Board for guidance in navigating the hobby.

Looks like you've got some of these covered already but this still might help you make better use of TER

So just some suggestions that might help learn the lay of the land:
1.  Check out the newbie board; lots of good info there
2.  Get the VIP membership so you can see the review details and have access to the PM system
3.  Spend some time learning how to use the search functions for both reviews and the discussion board so you can identify ladies you would be interested in seeing based on the criteria that matter most to you (ex: looks, menu, rates, etc.)
4.  Figure out what kind of verification the ladies you would like to see require and how you can meet those requirements.  Some ladies are very particular.  Others are more flexible.  It's OK to contact them about it if you are not sure; just remember to be discreet.  Any  explicit questions will likely get you disconnect or otherwise ignored.
5.  Some ladies advertise here or on other sites that they are newbie friendly; keep an eye out for that.
6.  Consider joining a site such as P411 that pre-screens potential clients.  Some escorts will accept membership in such sites as satisfactory verification.
7.  If you are still puzzled by something after having done research, please feel free to ask questions.  I think for the most part we are willing to help out so long as we think you are not just freeloading on what others have learned.
8.  Develop a bit of a thick skin; some people are going to be jerks regardless.
9.  If an ad or offer looks TGTBT, it's probably TGTBT.
10. If you find yourself in any situation that doesn't feel quite right, trust your instincts and walk away.
11. As a newcomer, stick with well-reviewed ladies.  It's harder when you are inexperienced to figure out who the legit providers are from the fakes and scammers when the don't have reviews.