Midlife- I have a Cannondale Synapse and it fits great for me, I am also 5'2". The frame is 47 cm and I have long legs and a short torso. Unlike my last bike, I can actually shift and brake easily from the drops. My bike has the 700 wheels and it took me a while not to look at it as out of proportion. I do love that I can now steal my husband's tubes instead of having my own. My guess is the manufacturers use 700 wheels on the higher end bikes because there is more variety of quality rims? I haven't done the research on that though.

As for the back issues, that seems like a fit problem. Although my shoulder blades ache on long rides too. I think it is more the way I ride, I tend to really grip the hoods and the kiss of death- lock my elbows. I have to be aware of my own position on the bike, I am my own worst enemy.

The Ruby has 700 wheels, so it wouldn't fit your criteria if you cannot stand the 700's.