You have a good budget to work with. I would suggest test riding different materials and different geometries. Try different companies, Cannondale's Synapse in carbon will be different than a Trek Madone that will be different than Specialized Ruby.

You are happy with Giant, what about their upgraded women's bike? What changes do you want to have in your new bike? Better drivetrain? Different frame material? Different geometry? I guess what I am saying is tell us what is important to you, I could gush all day about my bike but really where would that get you?