I'll just pop in to say I'm 5'11.5" with a 34.25" inseam. Ride a 58cm CAAD10, and had a bike fitting three days ago because I as well always felt stretched out and uncomfortable...for 10K miles. I've alternated between the stock 110 stem and an 80, and always felt most comfortable with the 80. When I left the fitting, I went from a 45cm drop bar width to a 40 (recommended a 38 but that just felt too extreme), my saddle raised and moved back to a 9cm setback, and the 80mm stem. Because of weather, I've only managed to put 5 miles on this new set up. I've had a tendency to slam my saddle as far forward as possible. This will take some getting used to, but I'm anxious to see if these changes set well with me for longer rides. In the times I've used the 80 in the past, I never felt like the bike was twitchy or unstable.
The big changes are the saddle height and set back.