possibly swapping cassettes
Chrys, have you talked to your shop about possibly swapping cassettes to give you some larger gears? The Shimano 105 grupo comes as large as a 28 tooth. Some of the newer Campy stuff will go up to a 29. Or you could go to a triple ring in front. If you change the stuff when you first buy the bike it's cheaper than doing it later. (Learned that one the hard way.)
As for bike suggestions, I'm partial to steel. I've been riding a Bianchi bike for 6 years and love it. A good friend of mine just bought a Jamis. It's also a very nice bike, with decent parts, for not a whole lot of money.