Have you looked into the Zipp Service Course SL-70 bars? The reach in them is fairly short at 70mm.
FWIW...I'm 5'8" with a 30 inseam. I had two Cannondales and they were both 52's. I can't see myself on a 54cm Cannondale...I'd have no seat post showing.
Here is my 52cm...after I was fit. I have a longish torso...my stem is a 110mm and the reach on the Easton bars is 75mm (I think).