Thanks for the comments Badger, pet peeve or not it sure helped me see the bigger picture as I went back to the store. I went back and rode the 56cm and it was almost identical to the old20in. both in length and t/t - and in addition to the way it felt sitting on it. I didn't seem to be scrunched like I was beginning to feel on the "54" size I had purchased. It was a better fit for me. Unfortunately after riding both my 2010 7.5 and the 2013 7.7 back to back, I was surprised to find that even though new bike was much lighter, the ride seemed harsher on the new carbon bike, I could feel every bump and crack. I even traded back and forth twice to compare and it appeared to be true to me. I suppose it is the bigger tire size. 32 vs the 25 is the reason - perhaps that is all it is, but with the lower gearing in the 7.5 I can move the heaver bike up the hills with no problem.
But all of this was enough for me to decide that it wasn't the bike I wanted to keep. So I asked to ride the new Domane to compare, and I have to admit that I was blown away by how smooth the ride was, I read the reviews recently but though it was mostly hyperbole, but after riding it together with the FX 7.7. and my old FX 7.5 I decided it was true. It was smoother than anything I had ridden in my limited experience.
I returned the new 7.7 since it was only 1 week and 3 rides old and took home the Domane 4.1 with a stem change to help me sit a little higher and help my old age back adjust easier. I still have my old FX for casual riding or even some touring, but hoping I can get settled in on the new Domane and ride with the local groups and keep up a bit better. I have only ridden the FX more than 50 miles a few times and it is really, really hard to enjoy the longer rides. I hope I'm not setting my expectations too high to think my new bike will make it easier to enjoy the longer group rides...