I'd get something with a more upright position:
Schwinn Voyageur 1 Commute Women's Sport Hybrid Bike - 2014 - Hybrid Comfort Bikes


Step-through is nice as it is easier to mount and wear more types of clothing. Even better is with a chain guard. Then your pants are safe.

Removable front wheel? who wants to drag that around all day with your books and other stuff? I say get the week locks, and learn proper locking technique like:
Hal Grades Your Bike Locking 2014 (Part IV) on Vimeo