I am 5ft 1in and the more standover height that I could get, the better. Also check the bike weight. Specialized told me that the WSD bikes are usually slightly lighter than men's bikes due to women tend to be lighter in weight in proportion to height, so the company adjusted accordingly....maybe it will be the same for Trek?
As for the more upright position, I have found that the more I ride, the more I need to lower my handlebars. Unfortunately, I am so short that my bike handlebars are currently only level with my saddle, even with a negative 17 degree stem on my MTB. There were times where the hills were so steep that my front wheels would just spin in the air (even though I rode in a "crouched" position and on my saddle's nose). One of the more experienced riders said that I needed to lower my handlebars some more (hence, I installed a negative 17 degree stem on my MTB). Sure enough, that helped for both of my wheels to touch the dirt going up hill.
Also, I thought that my dream MTB would be a 29er (which worked great rolling over huge roots). But, the supertight switchbacks (which scare the hell out of me going downhill) work so much better with a 26er for me, that I am glad I ended up with a 26er. I will try out a 650B next though.
2014 Liv Lust
2013 Specialized Fate Expert with carbon wheelset (sold)
2012 Specialized Amira Elite
2010 Santa Cruz Juliana with R kit and Crampon pedals (sold)
2011 Specialized Ariel Sport,suspension post,Serfas Rx Women's Microfiber saddle (sold)