+1 on everything Lisa said. I love my touring bike and know that it can handle just about anything--I've used it for heavily loaded touring, for commuting, for charity rides and next month I'll be riding it in a triathlon (o.k. it's not ideal for that but I can't afford another bike so this will have to do!). It's not as light and zippy as a road bike, but it sounds like it would fit the bill for the roads that you are on regularly and for the types of riding you have in mind. The only problem you'll have is that finding them used isn't easy--they aren't the most common type of bike and in my experience people who get them tend to keep them. I've seen them from time to time on eBay and Craigslist, but you might have better luck letting local shops and clubs know what you're looking for so they can help you look.

Good luck!

Sarah