I'll stick up for Cannondale!
I've been riding Cannondales since my first M400 in 1991 and I have found their service and support to be second to none through four bike upgrades to my current 2001 Jekyll 700.
I love the Cannondales for the gorgeous frames and the simple, yet attractive paint schemes. I have never had a problem with aluminum being too stiff, but maybe that has to do with the fact that I'm a beefy sucker!
Anyway, Try our and test ride everything you can and you will find exactly what you are looking for eventually!