I've got a Salsa Vaya that sounds like it'd be right up your alley. It does have drop bars as do most all road bikes but I feel very comfortable on our fire roads and have even done a small amount of single track. Wouldn't get that bike for that of course. Most folks ride on the tops and hoods of the drop bar and I find the hood position much more comfortable than the bar ends I've used on straight bar mountain bikes.There's a bunch of cyclocross and emerging "gravel" bikes such as the Spesh Diverge which a good friend just got for just what you described and he loves his.