I seem to recall that Cannondale's WSD models aren't really all that different in geometry from the men's...mostly they will use shorter-reach shifters and different saddles. So the women's 44cm SuperSix may be a really good fit for you, since the top tube/reach is quite a bit longer than the Synapse...which is awesome for us long-middled types.

Would you be looking at the Rival 4 package? I really like mine. I'm pretty much sold on SRAM.