Littlebit, where are you located? I live in northwest Ohio and would be happy to let you ride my small 650 wheeled bikes.

I'm 5'0"+1/2" tall (heh, the smallest coffee at Starbucks is a tall, so I'm a tall). I'd be very surprised if a 46-48 frame would fit someone our height - the top tubes are just too long. I have never considered a bike with 700 wheels.

My first bike was professionally fitted at a Detroit suburb bike shop. I had narrowed my choices down to a few bikes (including a Giant) but according to the fitting all my favorites were too big for me. They ordered me a mid range Cannondale R800 WSD size 40 cm with a 48.5 cm top tube and a 75 seat tube angle. This was back in 2002 - it seems that there are even fewer mid to higher end bikes in very small sizes today. I later bought a Seven titanium road bike which is a size 44 cm with a 48.5 cm top tube and a 75.5 seat tube angle. I ride over 6,000 miles a year so obviously these bikes fit me and are comfortable. I've taken advantage of additional fittings at triathlon events and the adjustments are very minor.

You mentioned you want carbon but don't mention a budget but you seem prepared to spend ... I think you should consider custom. The Orbea Diva 46 has a 74 seat tube angle but a 502 top tube which is too long for me. Scott Contessa xxs - also a 505 top tube. Specialized Ruby Pro just under 500 (496).

I'll be interested in hearing how the search ends ... please keep us posted.