Originally Posted by
am0n
looking at gear-calculator it's just a smaller step at the low end
Cassettes are easy to change and are considered wear items, so don't choose a bike or a groupset based on the cassette -- the LBS might even change swap the one that comes standard on the bike for any one you want. I'd encourage you to spring for 105 if you can, but not the end of the world if you can't.
Originally Posted by
am0n
What about the Specialized Allez Elite?
It's race geometry not endurance geometry -- take it for a ride and see how you like it. Should feel quite different than the Diverge.